sartre: Recent Episodes

View Details

LMR COOyrics I'll start this off Without any words I got so high I scratched 'till I bled I love myself Better than you I know it's wrong So what should I do? The finest day That I've ever had Was when I learned To cry on command I love myself Better than you I know it's wrong So what should I do? I'm on a plain I can't complain I'm on a plain My mother died Every night It's safe to say Quote me on that I love myself Better than you I know it's wrong So what should I do? The black sheep got Blackmailed again Forgot to put On the zip code I love myself Better than you I know it's wrong So what should I do? I'm on a plain I can't complain I'm on a plain Somewhere I have heard this before In a dream my memory has stored As a defense I'm neutered and spayed What the hell am I trying to say? It is now time To make it unclear To write off lines That don't make sense I love myself Better than you I know it's wrong So what should I do? And one more special Message to go And then I'm done And I can go home I love myself Better than you I know it's wrong So what should I do? I'm on a plain I can't complain I'm on a plain

People dying for no reason at all Age is no difference or if you're large or small Families been torn apart Doesn't have to be this way Some people just have no heart It's happening every day Pure massacre Pure massacre Pure massacre Pure massacre Machine guns pumping Hearts thumping Death is all around yeah People crying for freedom No one hears the sound oh Pure massacre Pure massacre Pure massacre Pure massacre alright There's people crying There's people dying But someone's taken it all Yeah Machine guns pumping, Hearts thumping, Death is all around, People crying for freedom No one hears the sound Pure massacreL2DOSONG PYN APO COMENT PHIL

View Details

21 Sartre on _Bad Faith_ bob solomon.mp3 subido я не задумывалась об этом как-то не задумывался Я всё это я считаю что всё это меня не касается как-то всё это прошло мимо моего сознания всегда не задумываюсь потому как своих я я мог сколько мог пережил Я уже если описать если мы все мухи Все круги ада уже пошёл я уже был на том свете не раз я уже Поэтому очередной раз я готов в любое время уже с этим уже смирился уже в моём положении мне всегда спрашивали почему вы не повесились этом духе мне задавали вопросы не повесился Ну я конечно если бы я был стандартный или повеситься самой вот это вот приключилось как сейчас вот пишу профессора это вот эти вот эти все эти все преследованиях чтобы отправили меня всю жизнь человека везде может быть неожиданно смотрит кошмары I didn’t think about it somehow I didn’t think about it All this I think that all this doesn’t concern me somehow all this passed by my consciousness I always don’t think because I could have survived my own as much as I could. All the circles of hell have already gone I have already been in the next world more than once I have already So ​​once again I am ready at any time I have already resigned myself to this already in my position I was always asked why you did not hang yourself in this spirit I was asked questions I did not hang myself Well, of course, if whether I was a standard one or hang myself this is what happened, as now I am writing to the professor, these are these all these all these persecutions to send me all the life of a person everywhere, maybe suddenly nightmares are looking,ll kas megadeth Ukrainian that I myself and I, I Vsevolod already sorted it out there in every way I spoke I put the institute of linguistics there on the sixth Ukrainian movi Well, I did not understand, we want to go Well, I thought with this for the sake of his neighbors in our apple cheese and apples there I sat on business trips I have not met in Kharkiv, there is already a sense of attention shorter chaplains wires to a maniac just a set of letters and wanted a delicate what it means when you were a child of artificially created 33 47 I ate this 33 young my older brother Stepan during hunger or people Hungry communicate and settled down warned not to go out 120 series you are sitting there, they are sitting there kalachiki do ate and mother it is dawn till dawn on the collective farm it was considered a disease it will pass a piece of black some kind of bread there will carry the atoms so they ate in the districts there they climbed all this there at home Close it all sit hungry looking out the window crying Little Red Riding Hood, of course, is always a pity of course, without hesitation, because how to describe if we have already gone to everyone, I was already in the light more than once. already thought once again I am ready at any time already already resigned to this already in my position I was always asked by Mitsubishi Russian Why did you not hang yourself in this spirit did not ask the question did not hang yourself Well, of course I was a standard one or to hang myself, this happened like now here I am writing to the professor this is to find stress and all these all these persecutions to send me this is the whole life I was deceived they wiped out considered a person everywhere maybe suddenly looks nightmares as normal can be in the sense that these are all like not mental sexual specially mentally inferiority friends now versions based on this, that's all, that's what I’m already there on the brains all sorts of valves put there brains fixed there some diseases were fixed by a lawyer proved that I’m sick And what to say Great To shoot no matter the main thing is nightmares how las diferentez posturas украинская что я и сам я я Всеволод уже там разбирал по-всякому разговариваю поставил там институт языкознания там на шестую украинский мови Ну так я не разобрал хотим поехать Ну я думал с таким ради его соседи в нашем яблочный сыр и яблоки там я сидел в командировках я не встречала в Харькове это там уже смысла внимания короче капелланы провода на маньяка просто набор букв и хотела щекотливое что у нас значит когда вы были ребёнком искусственно созданных 33 47 я вот это 33 молодым моего старшего брата Степана съели во время голода или люди Голодные общаюсь и осели предупреждала не выходи 120 серия тебя сидят они там калачики делайте питался и мать это зари до зари в колхозе считались болезнь это пройдёт кусок черного какой-то там пронесёт хлеба атомы тем питались в районах там лазили там всё это там дома Закрой это всё сиди голодный в окно смотрит плачу Красная шапочка конечно всегда жалко конечно не задумываясь потому как описать если мы Всем уже пошёл я уже был потом свете не раз я уже подумал очередной раз я готов в любое время уже с этим уже смирился уже в моём положении мне всегда вас спрашивали Mitsubishi русского Почему вы не повесились этом духе не задавали вопрос не повесился Ну я конечно себя был стандартный или повеситься самой вот это вот приключилось как сейчас вот пишу профессора это вот найти стресс и вот эти все эти все преследования чтобы отправили меня это самое всю жизнь Меня обманули вытирали считали человека везде может быть неожиданно смотрит кошмары как нормальный может быть в смысле что меня вот эти вот все как не психическое сексуальные специально психически ущербности друзья теперь версии на базе это вот всё вот этим я вот уже там на мозги всякие клапаны ставили там мозги зафиксировали там зафиксировали какие-то болезни адвокатом доказал что я больной А что говорить Здорово Расстрелять неважно главное кошмары как

View Details

giants of philosophy я не задумывалась об этом как-то не задумывался Я всё это я считаю что всё это меня не касается как-то всё это прошло мимо моего сознания всегда не задумываюсь потому как своих я я мог сколько мог пережил Я уже если описать если мы все мухи Все круги ада уже пошёл я уже был на том свете не раз я уже Поэтому очередной раз я готов в любое время уже с этим уже смирился уже в моём положении мне всегда спрашивали почему вы не повесились этом духе мне задавали вопросы не повесился Ну я конечно если бы я был стандартный или повеситься самой вот это вот приключилось как сейчас вот пишу профессора это вот эти вот эти все эти все преследованиях чтобы отправили меня всю жизнь человека везде может быть неожиданно смотрит кошмары I didn’t think about it somehow I didn’t think about it All this I think that all this doesn’t concern me somehow all this passed by my consciousness I always don’t think because I could have survived my own as much as I could. All the circles of hell have already gone I have already been in the next world more than once I have already So ​​once again I am ready at any time I have already resigned myself to this already in my position I was always asked why you did not hang yourself in this spirit I was asked questions I did not hang myself Well, of course, if whether I was a standard one or hang myself this is what happened, as now I am writing to the professor, these are these all these all these persecutions to send me all the life of a person everywhere, maybe suddenly nightmares are looking,ll kas megadeth Ukrainian that I myself and I, I Vsevolod already sorted it out there in every way I spoke I put the institute of linguistics there on the sixth Ukrainian movi Well, I did not understand, we want to go Well, I thought with this for the sake of his neighbors in our apple cheese and apples there I sat on business trips I have not met in Kharkiv, there is already a sense of attention shorter chaplains wires to a maniac just a set of letters and wanted a delicate what it means when you were a child of artificially created 33 47 I ate this 33 young my older brother Stepan during hunger or people Hungry communicate and settled down warned not to go out 120 series you are sitting there, they are sitting there kalachiki do ate and mother it is dawn till dawn on the collective farm it was considered a disease it will pass a piece of black some kind of bread there will carry the atoms so they ate in the districts there they climbed all this there at home Close it all sit hungry looking out the window crying Little Red Riding Hood, of course, is always a pity of course, without hesitation, because how to describe if we have already gone to everyone, I was already in the light more than once. already thought once again I am ready at any time already already resigned to this already in my position I was always asked by Mitsubishi Russian Why did you not hang yourself in this spirit did not ask the question did not hang yourself Well, of course I was a standard one or to hang myself, this happened like now here I am writing to the professor this is to find stress and all these all these persecutions to send me this is the whole life I was deceived they wiped out considered a person everywhere maybe suddenly looks nightmares as normal can be in the sense that these are all like not mental sexual specially mentally inferiority friends now versions based on this, that's all, that's what I’m already there on the brains all sorts of valves put there brains fixed there some diseases were fixed by a lawyer proved that I’m sick And what to say Great To shoot no matter the main thing is nightmares how las diferentez posturas украинская что я и сам я я Всеволод уже там разбирал по-всякому разговариваю поставил там институт языкознания там на шестую украинский мови Ну так я не разобрал хотим поехать Ну я думал с таким ради его соседи в нашем яблочный сыр и яблоки там я сидел в командировках я не встречала в Харькове это там уже смысла внимания короче капелланы провода на маньяка просто набор букв и хотела щекотливое что у нас значит когда вы были ребёнком искусственно созданных 33 47 я вот это 33 молодым моего старшего брата Степана съели во время голода или люди Голодные общаюсь и осели предупреждала не выходи 120 серия тебя сидят они там калачики делайте питался и мать это зари до зари в колхозе считались болезнь это пройдёт кусок черного какой-то там пронесёт хлеба атомы тем питались в районах там лазили там всё это там дома Закрой это всё сиди голодный в окно смотрит плачу Красная шапочка конечно всегда жалко конечно не задумываясь потому как описать если мы Всем уже пошёл я уже был потом свете не раз я уже подумал очередной раз я готов в любое время уже с этим уже смирился уже в моём положении мне всегда вас спрашивали Mitsubishi русского Почему вы не повесились этом духе не задавали вопрос не повесился Ну я конечно себя был стандартный или повеситься самой вот это вот приключилось как сейчас вот пишу профессора это вот найти стресс и вот эти все эти все преследования чтобы отправили меня это самое всю жизнь Меня обманули вытирали считали человека везде может быть неожиданно смотрит кошмары как нормальный может быть в смысле что меня вот эти вот все как не психическое сексуальные специально психически ущербности друзья теперь версии на базе это вот всё вот этим я вот уже там на мозги всякие клапаны ставили там мозги зафиксировали там зафиксировали какие-то болезни адвокатом доказал что я больной А что говорить Здорово Расстрелять неважно главное кошмары как

View Details

Las grandes pontenciaa estan el PELIGRO y peligro de Muerte repentiana..27 08.2021.a laa 09:04 AM 24 views27 Aug 2021

1

0

SHARE

SAVE

Fedora Matos Feliz 102 subscribers

2 Comments faridjabba Add a public comment... faridjabba faridjabba 0 seconds ago hola, ke bueno, podrias hacer un video sobre la Plan+demia?cuanto mas crees que durara lo de la plan+demia y lo de las mascaras? estan obligatorias en Alemania?

Tere Herrera Tere Herrera 1 day ago Amén 🙏

Fedora Matos Feliz Fedora Matos Feliz 3 days ago Alemannia y laa grades pontenciaa estan el PELIGRO y peligro de Muerte repentiana..27 08.2021.a laa 09:04 AM

View Details

Auteurs français, Citations CITATIONS DE SARTRE Jean-Paul Sartre, existentialisme

Les citations philosophiques de Jean-Paul Sartre Table des Matières [Cacher]

1 Les citations philosophiques de Jean-Paul Sartre 2 Sartre et l’existence : 3 Sartre et la liberté : 4 Sartre et la conscience : 5 Sartre et autrui : 6 Sartre et le corps : 7 Sartre et l’amour : 8 Sartre, la violence et la guerre : 9 Sartre, Dieu et l’athéisme : 9.1 Voir les articles sur Sartre : 9.2 Tous les articles sur Sartre 9.3 La philosophie de Sartre 9.4 La morale de Sartre 9.5 L’existentialisme est un humanisme de Sartre 9.6 L’existence précède l’essence 9.7 La mauvaise foi dans l’oeuvre de Sartre 9.8 Analyse de la Nausée 9.9 L’Etre et le Néant Jean-Paul Sartre est le philosophe français le plus lu et le plus commenté dans le monde. Fondateur de l’existentialisme, son œuvre prend pied chez Kierkegaard, Heidegger et Husserl principalement.

Auteur de théâtre, de roman et de manifestes politiques, la diversité de son œuvre, alliée à l’aridité de sa terminologie, rendent sa philosophie complexe à appréhender. Voici quelques citations pour saisir l’essentiel de sa philosophie : [ad#ad-5]

Sartre et l’existence : – “L’existence précède l’essence“

– “On meurt toujours trop tôt – ou trop tard. Et cependant la vie est là, terminée. Tu n’es rien d’autre que ta vie”

– “Qu’est-ce qu’exister ? Se boire sans soif”

– “L’existence précède l’essence. Cela signifie que l’homme existe d’abord, se rencontre, surgit dans le monde, et qu’il se définit ensuite”

Sartre et la liberté : – “L’homme est condamné à être libre“

– “L’angoisse est le vertige de la liberté”

– “Seuls les actes décident de ce qu’on a voulu”

– “On peut toujours faire quelque chose de ce qu’on a fait de nous”

– “Ne pas choisir, c’est encore choisir”

– “L’homme n’est rien d’autre que ce qu’il se fait”

– “Choix et conscience sont une seule et même chose”

– “Chaque homme doit inventer son chemin”

– “En fait, nous sommes une liberté qui choisit, mais nous ne choisissons pas d’être libres : nous sommes condamnés à la liberté”

– “Je construis l’universel en me choisissant; je le construis en comprenant le projet de tout autre homme, de quelque époque qu’il soit”

– “Etre condamné à être libre, cela signifie qu’on ne saurait trouver à ma liberté d’autres limites qu’elle-même”

– “C’est dans l’échec que l’on doit agir”

– “Agir, c’est modifier la figure du monde”

Sartre et la conscience : – “Etre une conscience c’est s’éclater vers le monde”

– “La conscience se constitue elle-même en même temps qu’elle se constitue comme conscience de l’autre”

– “La conscience est en réalité une conscience de conscience, car pour être conscience du monde; la conscience doit aussi être conscience d’elle-même”

Sartre et autrui : – “Alors, c’est ça l’enfer. Je n’aurais jamais cru… Vous vous rappelez: le soufre, le bûcher, le gril… Ah! quelle plaisanterie. Pas besoin de gril : l’enfer, c’est les Autres”

– “Autrui, c’est ce moi qui n’est pas moi”

– “Je ne constitue pas autrui, je le rencontre”

– “Ma chute originelle, c’est l’existence d’autrui”

– “Le conflit est le sens originel du Pour-Autrui”

– “Ainsi, autrui est d’abord pour moi l’être pour qui je suis objet”

– “Ma chute originelle, c’est l’existence de l’autre”

– “On me voit donc je suis”

– “Le Pour-Soi est toujours aussi un Pour-Autrui”

– “Il n’y a d’oppression que d’une liberté par une liberté”

– “Un homme peut toujours faire quelque chose de ce qu’on a fait de lui”

Sartre et le corps : – “Le corps n’est pas uni à la conscience, il est tout entier psychique”

– “Le corps est un Pour-Soi, et non un En-Soi dans le Pour-Soi”

– “La conscience existe dans son corps”

Sartre et l’amour : – “Aimer est, dans son essence, le projet de se faire aimer”

– “Un amour, une carrière, une révolution : autant d’entreprises que l’on commence en ignorant leur issue”

– “C’est là le fond de la joie d’amour, lorsqu’elle existe: nous sentir justifiés d’exister”

– “Aimer est le projet de se faire aimer”

– “L’idéal de l’entreprise amoureuse est la liberté aliénée : chacun veut que la liberté de l’autre s’aliène”

– “Ma tentative originelle pour me saisir de la subjectivité libre de l’autre à travers son objectité pour moi est le désir sexuel”

– “L’être qui désire, c’est la conscience se faisant corps”

– “Le désir s’exprime par la caresse comme la pensée par le langage”

– “Le plaisir est la mort et l’échec du désir”

– “La maternité est la possibilité ontologique de la fraternité”

Sartre, la violence et la guerre : – “La violence n’est pas un moyen parmi d’autres d’atteindre la fin, mais le choix délibéré d’atteindre la fin par n’importe quel moyen”

– “A moitié victime, à moitié complice, comme tout le monde”

– “La guerre, on ne la fait pas : c’est elle qui nous fait”

– “Quand les riches se font la guerre, ce sont les pauvres qui meurent”

Sartre, Dieu et l’athéisme : – “Dieu est mort, mais l’homme n’est pas, pour autant, devenu athée. Ce silence du transcendant, joint à la permanence du besoin religieux chez l’homme moderne, voilà la grande affaire aujourd’hui comme hier”

– “L’absence de Dieu n’est pas la fermeture, c’est ouverture sur l’infini”

– “Dieu, c’est la solitude des hommes… Si Dieu existe, l’homme est néant”

Voir les articles sur Sartre : Tous les articles sur Sartre La philosophie de Sartre La morale de Sartre L’existentialisme est un humanisme de Sartre L’existence précède l’essence La mauvaise foi dans l’oeuvre de Sartre Analyse de la Nausée L’Etre et le Néant 21 Facebook Twitter Pinterest GOOGLE + LINKEDIN EMAIL You may also like 21 Comments GODIN 01/02/2011 à 18:31 Je m’intéresse beaucoup à la philosophie où pouurais-je commander des livres.

Merci

Danielle GODIN

RÉPONDRE philocours 02/02/2011 à 14:40 Bonjour Danielle,

je vous recommande le site abebooks.fr, très sérieux.

L’équipe La-Philosophie.com

RÉPONDRE gontrand 18/02/2011 à 12:59 j’adore les citations de Jean-Paul Sartre, le plus grands philosophe français ! il a tout compris sur la liberté, la métaphysique et la condition humaine. l’existentialisme est un humanisme m’a fait aimé la philosophie

RÉPONDRE dana 04/12/2011 à 11:23 Sartre s’est un grand philosophe

RÉPONDRE dana 04/12/2011 à 11:23 Sartre c’est un grand philosophe

RÉPONDRE Ping : Sartre : L’existentialisme est un humanisme (commentaire et résumé) Ping : La morale de Sartre Ping : Sartre et la liberté Ping : Sartre : L'enfer, c'est les autres Rudolf Daniel 17/04/2013 à 12:57 L’un des plus grands philosophes de l’histoire. Sartre, tu manques à l’humanité!

RÉPONDRE taylor 31/10/2013 à 12:42 l’homme est sa sagesse s’epanoui

RÉPONDRE LOCO 27/02/2014 à 02:28 “On me voit, donc je suis” Sartre Ce n’est pas vrai puisque tout ce qu’on voit et même tout ce qu’on expérimente n’est plus, c’est le passé, c’était. Alors “On me voit, donc j’étais” Je ne suis que dans ma conscience. J’ai conscience d’être mais je ne peux pas l’expérimenter. Expérience et conscience ne sont pas la même chose.

RÉPONDRE diabate 22/11/2014 à 21:18 je ve us avoir plus

RÉPONDRE Pauly 11/12/2015 à 09:28 Sartre c’est un grand Philosophe.

RÉPONDRE Christian Martial Poos 27/03/2016 à 22:44 De l’existentialisme à Autrui,en passant par le Néant et …Il ya que l’Etre diversifie les termes ,pour arriver à expliquer la marche du monde sans totalement se nier ,je veux dire ,réfuter qu’il est là pour obeir à sa progression dont il ignore l’issue

RÉPONDRE KOUIDER MAROUF 10/07/2016 à 15:00 conciliation du sujet et de l’objet:on ne peut parler de l’islamophobie uniquement si on est islamophobe ,aurait dit surement SARTRE.M

RÉPONDRE KOUIDER MAROUF 10/07/2016 à 15:08 conciliation du sjet et de l’objet:on ne peut parlerde l’islamophobie quand n’etant islamophobe ,aurait certainement dit jpSARTRE?le seul et unque philosophe(la presse française est marante quand elle glorifie un criminel de guerre BHL et le cite à tout bout de champs comme philosophe)qu elle arrete pour l’amour de la paix et la justice cette mascarade!avec toutes les tartres qu il a reçu sur la gueule….

RÉPONDRE Anonyme 11/09/2016 à 17:21 La philosophie de satre me donne toujour l’amour de vivre e de pouvoir atteindre mes fins car il dit: l’hom n’est rien d ce qu’il se fait . Sans Sartre la vie serai com 1mond sans âme me lov sartr

RÉPONDRE Anonyme 02/10/2016 à 20:34 homme comme d autres

RÉPONDRE Christian Bienvenu 15/12/2017 à 17:08 Je m’intéresse beaucoup à la philosophie de J.P SARTRE le plus grand philosophe français: car il a bien compris sur la violence et la guerre, quand aujourd’hui dans notre pays le riches se font la guerre, ce sont le pauvres qui meurent, ce vraix que la guerre, on ne la fait pas: mais c’est elle qui nous fait le pauvre. La violence et la guerre qui m’a fait aimé la philosophie de J.P SARTRE.

RÉPONDRE Mike 13/08/2018 à 15:24 “l’angoisse est le vertige de la liberté” est une citation de Soren Kierkegaard, me semble t-il.

RÉPONDRE Laisser un commentaire Votre adresse de messagerie ne sera pas publiée. Les champs obligatoires sont indiqués avec *

Commentaire

Nom * Adresse de messagerie * Site web La modération des commentaires est activée. Votre commentaire peut prendre un certain temps avant d’apparaître.

ARTICLES LES + LUS

Bac Philo Exemple de Dissertation Philosophique

Recherches Les Films Philosophiques

Bac Philo Bac Philosophie 2020 : Notre guide des révisions new york coronavirus Recherches Pandémie : Est-ce venu l’ère du technicisme ? Macron, un président en guerre contre le coronavirus Recherches Propos sur la guerre, ou la fabrique d’une illusion – Tribune

Philosophes Courants de la philosophie QUIZ PHILO quiz philo L’APP LA-PHILOSOPHIE.COM Application Philosophie Téléchargez notre application gratuite sur le Play Store

DERNIERS ARTICLES Les Films Philosophiques Que nous apprend l’expérience du virus ? Une approche philosophique de la maladie La Neuro-philosophie et le Transhumanisme Créon, héros tragique: Une lecture philosophique du mythe grec La philosophie de Heidegger: De l’étant à l’Etre More Stories

Recherches Le culte de la performance comme mode d’existence ? Plan du site Publicité / Contact QUI SOMMES-NOUS? Depuis 2008, la-philosophie.com agit pour la diffusion de la tradition et des grandes pensées philosophiques. Indépendant, le site est maintenu par une équipe d'anciens étudiants en sciences humaines, aujourd'hui professeurs ou journalistes. Les colonnes du site sont ouvertes aux contributions externes. Julien Josset, fondateur du site. La-Philosophie.com en bref La-Philosophie.com aide les élèves de terminales dans la préparation du bac, les élèves de classes prépa dans celle de leur concours, ceux de fac dans leurs recherches, et enfin tous les curieux de sciences humaines à étancher leur soif de savoir.

Le site couvre ainsi les grandes traditions philosophiques, des présocratiques aux philosophes contemporains, tout en essayant d’apporter une lecture philosophique au champ culturel en général, qu’il s’agisse de cinéma, de littérature, de politique ou de musique.

Qu’est-ce que la philosophie*? Etymologiquement, philosophie signifie amour de la sagesse. Avant d’être une discipline d’étude, il s’agit avant tout d’une certaine manière de voir le monde, de le questionner. Le principe fondateur de la philosophie est sans doute ainsi l’étonnement, qui provoque et suscite le questionnement. Ensuite, philosopher consiste à argumenter de manière rationnelle sur son étonnement.

• Nous avons publié plus de 700 articles, tous cherchant directement ou indirectement à répondre à cette question. Sachez avant tout qu’il n’existe pas de réponse unique à cette question.

PRINCIPAUX PHILOSOPHES Socrate, Platon, Aristote, Epicure, Descartes, Machiavel, Spinoza, Hobbes, Rousseau, Montesquieu, Kant, Schopenhauer, Hegel, Nietzsche, Marx, Freud, Sartre, Heidegger PARTENAIRES Cours de Droit La Filosofia (en espagnol) Philosophie Sorbonne The-Philosophy.com (en anglais) PROPULSÉ PAR WORDPRESS - LA-PHILOSOPHIE.COM - 2008-2020 MODIFIER LES PARAMÈTRES DE CONFIDENTIALITÉ

View Details

Auteurs français, Citations CITATIONS DE SARTRE Jean-Paul Sartre, existentialisme

Les citations philosophiques de Jean-Paul Sartre Table des Matières [Cacher]

1 Les citations philosophiques de Jean-Paul Sartre 2 Sartre et l’existence : 3 Sartre et la liberté : 4 Sartre et la conscience : 5 Sartre et autrui : 6 Sartre et le corps : 7 Sartre et l’amour : 8 Sartre, la violence et la guerre : 9 Sartre, Dieu et l’athéisme : 9.1 Voir les articles sur Sartre : 9.2 Tous les articles sur Sartre 9.3 La philosophie de Sartre 9.4 La morale de Sartre 9.5 L’existentialisme est un humanisme de Sartre 9.6 L’existence précède l’essence 9.7 La mauvaise foi dans l’oeuvre de Sartre 9.8 Analyse de la Nausée 9.9 L’Etre et le Néant Jean-Paul Sartre est le philosophe français le plus lu et le plus commenté dans le monde. Fondateur de l’existentialisme, son œuvre prend pied chez Kierkegaard, Heidegger et Husserl principalement.

Auteur de théâtre, de roman et de manifestes politiques, la diversité de son œuvre, alliée à l’aridité de sa terminologie, rendent sa philosophie complexe à appréhender. Voici quelques citations pour saisir l’essentiel de sa philosophie : [ad#ad-5]

Sartre et l’existence : – “L’existence précède l’essence“

– “On meurt toujours trop tôt – ou trop tard. Et cependant la vie est là, terminée. Tu n’es rien d’autre que ta vie”

– “Qu’est-ce qu’exister ? Se boire sans soif”

– “L’existence précède l’essence. Cela signifie que l’homme existe d’abord, se rencontre, surgit dans le monde, et qu’il se définit ensuite”

Sartre et la liberté : – “L’homme est condamné à être libre“

– “L’angoisse est le vertige de la liberté”

– “Seuls les actes décident de ce qu’on a voulu”

– “On peut toujours faire quelque chose de ce qu’on a fait de nous”

– “Ne pas choisir, c’est encore choisir”

– “L’homme n’est rien d’autre que ce qu’il se fait”

– “Choix et conscience sont une seule et même chose”

– “Chaque homme doit inventer son chemin”

– “En fait, nous sommes une liberté qui choisit, mais nous ne choisissons pas d’être libres : nous sommes condamnés à la liberté”

– “Je construis l’universel en me choisissant; je le construis en comprenant le projet de tout autre homme, de quelque époque qu’il soit”

– “Etre condamné à être libre, cela signifie qu’on ne saurait trouver à ma liberté d’autres limites qu’elle-même”

– “C’est dans l’échec que l’on doit agir”

– “Agir, c’est modifier la figure du monde”

Sartre et la conscience : – “Etre une conscience c’est s’éclater vers le monde”

– “La conscience se constitue elle-même en même temps qu’elle se constitue comme conscience de l’autre”

– “La conscience est en réalité une conscience de conscience, car pour être conscience du monde; la conscience doit aussi être conscience d’elle-même”

Sartre et autrui : – “Alors, c’est ça l’enfer. Je n’aurais jamais cru… Vous vous rappelez: le soufre, le bûcher, le gril… Ah! quelle plaisanterie. Pas besoin de gril : l’enfer, c’est les Autres”

– “Autrui, c’est ce moi qui n’est pas moi”

– “Je ne constitue pas autrui, je le rencontre”

– “Ma chute originelle, c’est l’existence d’autrui”

– “Le conflit est le sens originel du Pour-Autrui”

– “Ainsi, autrui est d’abord pour moi l’être pour qui je suis objet”

– “Ma chute originelle, c’est l’existence de l’autre”

– “On me voit donc je suis”

– “Le Pour-Soi est toujours aussi un Pour-Autrui”

– “Il n’y a d’oppression que d’une liberté par une liberté”

– “Un homme peut toujours faire quelque chose de ce qu’on a fait de lui”

Sartre et le corps : – “Le corps n’est pas uni à la conscience, il est tout entier psychique”

– “Le corps est un Pour-Soi, et non un En-Soi dans le Pour-Soi”

– “La conscience existe dans son corps”

Sartre et l’amour : – “Aimer est, dans son essence, le projet de se faire aimer”

– “Un amour, une carrière, une révolution : autant d’entreprises que l’on commence en ignorant leur issue”

– “C’est là le fond de la joie d’amour, lorsqu’elle existe: nous sentir justifiés d’exister”

– “Aimer est le projet de se faire aimer”

– “L’idéal de l’entreprise amoureuse est la liberté aliénée : chacun veut que la liberté de l’autre s’aliène”

– “Ma tentative originelle pour me saisir de la subjectivité libre de l’autre à travers son objectité pour moi est le désir sexuel”

– “L’être qui désire, c’est la conscience se faisant corps”

– “Le désir s’exprime par la caresse comme la pensée par le langage”

– “Le plaisir est la mort et l’échec du désir”

– “La maternité est la possibilité ontologique de la fraternité”

Sartre, la violence et la guerre : – “La violence n’est pas un moyen parmi d’autres d’atteindre la fin, mais le choix délibéré d’atteindre la fin par n’importe quel moyen”

– “A moitié victime, à moitié complice, comme tout le monde”

– “La guerre, on ne la fait pas : c’est elle qui nous fait”

– “Quand les riches se font la guerre, ce sont les pauvres qui meurent”

Sartre, Dieu et l’athéisme : – “Dieu est mort, mais l’homme n’est pas, pour autant, devenu athée. Ce silence du transcendant, joint à la permanence du besoin religieux chez l’homme moderne, voilà la grande affaire aujourd’hui comme hier”

– “L’absence de Dieu n’est pas la fermeture, c’est ouverture sur l’infini”

– “Dieu, c’est la solitude des hommes… Si Dieu existe, l’homme est néant”

Voir les articles sur Sartre : Tous les articles sur Sartre La philosophie de Sartre La morale de Sartre L’existentialisme est un humanisme de Sartre L’existence précède l’essence La mauvaise foi dans l’oeuvre de Sartre Analyse de la Nausée L’Etre et le Néant 21 Facebook Twitter Pinterest GOOGLE + LINKEDIN EMAIL You may also like 21 Comments GODIN 01/02/2011 à 18:31 Je m’intéresse beaucoup à la philosophie où pouurais-je commander des livres.

Merci

Danielle GODIN

RÉPONDRE philocours 02/02/2011 à 14:40 Bonjour Danielle,

je vous recommande le site abebooks.fr, très sérieux.

L’équipe La-Philosophie.com

RÉPONDRE gontrand 18/02/2011 à 12:59 j’adore les citations de Jean-Paul Sartre, le plus grands philosophe français ! il a tout compris sur la liberté, la métaphysique et la condition humaine. l’existentialisme est un humanisme m’a fait aimé la philosophie

RÉPONDRE dana 04/12/2011 à 11:23 Sartre s’est un grand philosophe

RÉPONDRE dana 04/12/2011 à 11:23 Sartre c’est un grand philosophe

RÉPONDRE Ping : Sartre : L’existentialisme est un humanisme (commentaire et résumé) Ping : La morale de Sartre Ping : Sartre et la liberté Ping : Sartre : L'enfer, c'est les autres Rudolf Daniel 17/04/2013 à 12:57 L’un des plus grands philosophes de l’histoire. Sartre, tu manques à l’humanité!

RÉPONDRE taylor 31/10/2013 à 12:42 l’homme est sa sagesse s’epanoui

RÉPONDRE LOCO 27/02/2014 à 02:28 “On me voit, donc je suis” Sartre Ce n’est pas vrai puisque tout ce qu’on voit et même tout ce qu’on expérimente n’est plus, c’est le passé, c’était. Alors “On me voit, donc j’étais” Je ne suis que dans ma conscience. J’ai conscience d’être mais je ne peux pas l’expérimenter. Expérience et conscience ne sont pas la même chose.

RÉPONDRE diabate 22/11/2014 à 21:18 je ve us avoir plus

RÉPONDRE Pauly 11/12/2015 à 09:28 Sartre c’est un grand Philosophe.

RÉPONDRE Christian Martial Poos 27/03/2016 à 22:44 De l’existentialisme à Autrui,en passant par le Néant et …Il ya que l’Etre diversifie les termes ,pour arriver à expliquer la marche du monde sans totalement se nier ,je veux dire ,réfuter qu’il est là pour obeir à sa progression dont il ignore l’issue

RÉPONDRE KOUIDER MAROUF 10/07/2016 à 15:00 conciliation du sujet et de l’objet:on ne peut parler de l’islamophobie uniquement si on est islamophobe ,aurait dit surement SARTRE.M

RÉPONDRE KOUIDER MAROUF 10/07/2016 à 15:08 conciliation du sjet et de l’objet:on ne peut parlerde l’islamophobie quand n’etant islamophobe ,aurait certainement dit jpSARTRE?le seul et unque philosophe(la presse française est marante quand elle glorifie un criminel de guerre BHL et le cite à tout bout de champs comme philosophe)qu elle arrete pour l’amour de la paix et la justice cette mascarade!avec toutes les tartres qu il a reçu sur la gueule….

RÉPONDRE Anonyme 11/09/2016 à 17:21 La philosophie de satre me donne toujour l’amour de vivre e de pouvoir atteindre mes fins car il dit: l’hom n’est rien d ce qu’il se fait . Sans Sartre la vie serai com 1mond sans âme me lov sartr

RÉPONDRE Anonyme 02/10/2016 à 20:34 homme comme d autres

RÉPONDRE Christian Bienvenu 15/12/2017 à 17:08 Je m’intéresse beaucoup à la philosophie de J.P SARTRE le plus grand philosophe français: car il a bien compris sur la violence et la guerre, quand aujourd’hui dans notre pays le riches se font la guerre, ce sont le pauvres qui meurent, ce vraix que la guerre, on ne la fait pas: mais c’est elle qui nous fait le pauvre. La violence et la guerre qui m’a fait aimé la philosophie de J.P SARTRE.

RÉPONDRE Mike 13/08/2018 à 15:24 “l’angoisse est le vertige de la liberté” est une citation de Soren Kierkegaard, me semble t-il.

RÉPONDRE Laisser un commentaire Votre adresse de messagerie ne sera pas publiée. Les champs obligatoires sont indiqués avec *

Commentaire

Nom * Adresse de messagerie * Site web La modération des commentaires est activée. Votre commentaire peut prendre un certain temps avant d’apparaître.

ARTICLES LES + LUS

Bac Philo Exemple de Dissertation Philosophique

Recherches Les Films Philosophiques

Bac Philo Bac Philosophie 2020 : Notre guide des révisions new york coronavirus Recherches Pandémie : Est-ce venu l’ère du technicisme ? Macron, un président en guerre contre le coronavirus Recherches Propos sur la guerre, ou la fabrique d’une illusion – Tribune

Philosophes Courants de la philosophie QUIZ PHILO quiz philo L’APP LA-PHILOSOPHIE.COM Application Philosophie Téléchargez notre application gratuite sur le Play Store

DERNIERS ARTICLES Les Films Philosophiques Que nous apprend l’expérience du virus ? Une approche philosophique de la maladie La Neuro-philosophie et le Transhumanisme Créon, héros tragique: Une lecture philosophique du mythe grec La philosophie de Heidegger: De l’étant à l’Etre More Stories

Recherches Le culte de la performance comme mode d’existence ? Plan du site Publicité / Contact QUI SOMMES-NOUS? Depuis 2008, la-philosophie.com agit pour la diffusion de la tradition et des grandes pensées philosophiques. Indépendant, le site est maintenu par une équipe d'anciens étudiants en sciences humaines, aujourd'hui professeurs ou journalistes. Les colonnes du site sont ouvertes aux contributions externes. Julien Josset, fondateur du site. La-Philosophie.com en bref La-Philosophie.com aide les élèves de terminales dans la préparation du bac, les élèves de classes prépa dans celle de leur concours, ceux de fac dans leurs recherches, et enfin tous les curieux de sciences humaines à étancher leur soif de savoir.

Le site couvre ainsi les grandes traditions philosophiques, des présocratiques aux philosophes contemporains, tout en essayant d’apporter une lecture philosophique au champ culturel en général, qu’il s’agisse de cinéma, de littérature, de politique ou de musique.

Qu’est-ce que la philosophie*? Etymologiquement, philosophie signifie amour de la sagesse. Avant d’être une discipline d’étude, il s’agit avant tout d’une certaine manière de voir le monde, de le questionner. Le principe fondateur de la philosophie est sans doute ainsi l’étonnement, qui provoque et suscite le questionnement. Ensuite, philosopher consiste à argumenter de manière rationnelle sur son étonnement.

• Nous avons publié plus de 700 articles, tous cherchant directement ou indirectement à répondre à cette question. Sachez avant tout qu’il n’existe pas de réponse unique à cette question.

PRINCIPAUX PHILOSOPHES Socrate, Platon, Aristote, Epicure, Descartes, Machiavel, Spinoza, Hobbes, Rousseau, Montesquieu, Kant, Schopenhauer, Hegel, Nietzsche, Marx, Freud, Sartre, Heidegger PARTENAIRES Cours de Droit La Filosofia (en espagnol) Philosophie Sorbonne The-Philosophy.com (en anglais) PROPULSÉ PAR WORDPRESS - LA-PHILOSOPHIE.COM - 2008-2020 MODIFIER LES PARAMÈTRES DE CONFIDENTIALITÉ

View Details

Auteurs français, Citations CITATIONS DE SARTRE Jean-Paul Sartre, existentialisme

Les citations philosophiques de Jean-Paul Sartre Table des Matières [Cacher]

1 Les citations philosophiques de Jean-Paul Sartre 2 Sartre et l’existence : 3 Sartre et la liberté : 4 Sartre et la conscience : 5 Sartre et autrui : 6 Sartre et le corps : 7 Sartre et l’amour : 8 Sartre, la violence et la guerre : 9 Sartre, Dieu et l’athéisme : 9.1 Voir les articles sur Sartre : 9.2 Tous les articles sur Sartre 9.3 La philosophie de Sartre 9.4 La morale de Sartre 9.5 L’existentialisme est un humanisme de Sartre 9.6 L’existence précède l’essence 9.7 La mauvaise foi dans l’oeuvre de Sartre 9.8 Analyse de la Nausée 9.9 L’Etre et le Néant Jean-Paul Sartre est le philosophe français le plus lu et le plus commenté dans le monde. Fondateur de l’existentialisme, son œuvre prend pied chez Kierkegaard, Heidegger et Husserl principalement.

Auteur de théâtre, de roman et de manifestes politiques, la diversité de son œuvre, alliée à l’aridité de sa terminologie, rendent sa philosophie complexe à appréhender. Voici quelques citations pour saisir l’essentiel de sa philosophie : [ad#ad-5]

Sartre et l’existence : – “L’existence précède l’essence“

– “On meurt toujours trop tôt – ou trop tard. Et cependant la vie est là, terminée. Tu n’es rien d’autre que ta vie”

– “Qu’est-ce qu’exister ? Se boire sans soif”

– “L’existence précède l’essence. Cela signifie que l’homme existe d’abord, se rencontre, surgit dans le monde, et qu’il se définit ensuite”

Sartre et la liberté : – “L’homme est condamné à être libre“

– “L’angoisse est le vertige de la liberté”

– “Seuls les actes décident de ce qu’on a voulu”

– “On peut toujours faire quelque chose de ce qu’on a fait de nous”

– “Ne pas choisir, c’est encore choisir”

– “L’homme n’est rien d’autre que ce qu’il se fait”

– “Choix et conscience sont une seule et même chose”

– “Chaque homme doit inventer son chemin”

– “En fait, nous sommes une liberté qui choisit, mais nous ne choisissons pas d’être libres : nous sommes condamnés à la liberté”

– “Je construis l’universel en me choisissant; je le construis en comprenant le projet de tout autre homme, de quelque époque qu’il soit”

– “Etre condamné à être libre, cela signifie qu’on ne saurait trouver à ma liberté d’autres limites qu’elle-même”

– “C’est dans l’échec que l’on doit agir”

– “Agir, c’est modifier la figure du monde”

Sartre et la conscience : – “Etre une conscience c’est s’éclater vers le monde”

– “La conscience se constitue elle-même en même temps qu’elle se constitue comme conscience de l’autre”

– “La conscience est en réalité une conscience de conscience, car pour être conscience du monde; la conscience doit aussi être conscience d’elle-même”

Sartre et autrui : – “Alors, c’est ça l’enfer. Je n’aurais jamais cru… Vous vous rappelez: le soufre, le bûcher, le gril… Ah! quelle plaisanterie. Pas besoin de gril : l’enfer, c’est les Autres”

– “Autrui, c’est ce moi qui n’est pas moi”

– “Je ne constitue pas autrui, je le rencontre”

– “Ma chute originelle, c’est l’existence d’autrui”

– “Le conflit est le sens originel du Pour-Autrui”

– “Ainsi, autrui est d’abord pour moi l’être pour qui je suis objet”

– “Ma chute originelle, c’est l’existence de l’autre”

– “On me voit donc je suis”

– “Le Pour-Soi est toujours aussi un Pour-Autrui”

– “Il n’y a d’oppression que d’une liberté par une liberté”

– “Un homme peut toujours faire quelque chose de ce qu’on a fait de lui”

Sartre et le corps : – “Le corps n’est pas uni à la conscience, il est tout entier psychique”

– “Le corps est un Pour-Soi, et non un En-Soi dans le Pour-Soi”

– “La conscience existe dans son corps”

Sartre et l’amour : – “Aimer est, dans son essence, le projet de se faire aimer”

– “Un amour, une carrière, une révolution : autant d’entreprises que l’on commence en ignorant leur issue”

– “C’est là le fond de la joie d’amour, lorsqu’elle existe: nous sentir justifiés d’exister”

– “Aimer est le projet de se faire aimer”

– “L’idéal de l’entreprise amoureuse est la liberté aliénée : chacun veut que la liberté de l’autre s’aliène”

– “Ma tentative originelle pour me saisir de la subjectivité libre de l’autre à travers son objectité pour moi est le désir sexuel”

– “L’être qui désire, c’est la conscience se faisant corps”

– “Le désir s’exprime par la caresse comme la pensée par le langage”

– “Le plaisir est la mort et l’échec du désir”

– “La maternité est la possibilité ontologique de la fraternité”

Sartre, la violence et la guerre : – “La violence n’est pas un moyen parmi d’autres d’atteindre la fin, mais le choix délibéré d’atteindre la fin par n’importe quel moyen”

– “A moitié victime, à moitié complice, comme tout le monde”

– “La guerre, on ne la fait pas : c’est elle qui nous fait”

– “Quand les riches se font la guerre, ce sont les pauvres qui meurent”

Sartre, Dieu et l’athéisme : – “Dieu est mort, mais l’homme n’est pas, pour autant, devenu athée. Ce silence du transcendant, joint à la permanence du besoin religieux chez l’homme moderne, voilà la grande affaire aujourd’hui comme hier”

– “L’absence de Dieu n’est pas la fermeture, c’est ouverture sur l’infini”

– “Dieu, c’est la solitude des hommes… Si Dieu existe, l’homme est néant”

Voir les articles sur Sartre : Tous les articles sur Sartre La philosophie de Sartre La morale de Sartre L’existentialisme est un humanisme de Sartre L’existence précède l’essence La mauvaise foi dans l’oeuvre de Sartre Analyse de la Nausée L’Etre et le Néant 21 Facebook Twitter Pinterest GOOGLE + LINKEDIN EMAIL You may also like 21 Comments GODIN 01/02/2011 à 18:31 Je m’intéresse beaucoup à la philosophie où pouurais-je commander des livres.

Merci

Danielle GODIN

RÉPONDRE philocours 02/02/2011 à 14:40 Bonjour Danielle,

je vous recommande le site abebooks.fr, très sérieux.

L’équipe La-Philosophie.com

RÉPONDRE gontrand 18/02/2011 à 12:59 j’adore les citations de Jean-Paul Sartre, le plus grands philosophe français ! il a tout compris sur la liberté, la métaphysique et la condition humaine. l’existentialisme est un humanisme m’a fait aimé la philosophie

RÉPONDRE dana 04/12/2011 à 11:23 Sartre s’est un grand philosophe

RÉPONDRE dana 04/12/2011 à 11:23 Sartre c’est un grand philosophe

RÉPONDRE Ping : Sartre : L’existentialisme est un humanisme (commentaire et résumé) Ping : La morale de Sartre Ping : Sartre et la liberté Ping : Sartre : L'enfer, c'est les autres Rudolf Daniel 17/04/2013 à 12:57 L’un des plus grands philosophes de l’histoire. Sartre, tu manques à l’humanité!

RÉPONDRE taylor 31/10/2013 à 12:42 l’homme est sa sagesse s’epanoui

RÉPONDRE LOCO 27/02/2014 à 02:28 “On me voit, donc je suis” Sartre Ce n’est pas vrai puisque tout ce qu’on voit et même tout ce qu’on expérimente n’est plus, c’est le passé, c’était. Alors “On me voit, donc j’étais” Je ne suis que dans ma conscience. J’ai conscience d’être mais je ne peux pas l’expérimenter. Expérience et conscience ne sont pas la même chose.

RÉPONDRE diabate 22/11/2014 à 21:18 je ve us avoir plus

RÉPONDRE Pauly 11/12/2015 à 09:28 Sartre c’est un grand Philosophe.

RÉPONDRE Christian Martial Poos 27/03/2016 à 22:44 De l’existentialisme à Autrui,en passant par le Néant et …Il ya que l’Etre diversifie les termes ,pour arriver à expliquer la marche du monde sans totalement se nier ,je veux dire ,réfuter qu’il est là pour obeir à sa progression dont il ignore l’issue

RÉPONDRE KOUIDER MAROUF 10/07/2016 à 15:00 conciliation du sujet et de l’objet:on ne peut parler de l’islamophobie uniquement si on est islamophobe ,aurait dit surement SARTRE.M

RÉPONDRE KOUIDER MAROUF 10/07/2016 à 15:08 conciliation du sjet et de l’objet:on ne peut parlerde l’islamophobie quand n’etant islamophobe ,aurait certainement dit jpSARTRE?le seul et unque philosophe(la presse française est marante quand elle glorifie un criminel de guerre BHL et le cite à tout bout de champs comme philosophe)qu elle arrete pour l’amour de la paix et la justice cette mascarade!avec toutes les tartres qu il a reçu sur la gueule….

RÉPONDRE Anonyme 11/09/2016 à 17:21 La philosophie de satre me donne toujour l’amour de vivre e de pouvoir atteindre mes fins car il dit: l’hom n’est rien d ce qu’il se fait . Sans Sartre la vie serai com 1mond sans âme me lov sartr

RÉPONDRE Anonyme 02/10/2016 à 20:34 homme comme d autres

RÉPONDRE Christian Bienvenu 15/12/2017 à 17:08 Je m’intéresse beaucoup à la philosophie de J.P SARTRE le plus grand philosophe français: car il a bien compris sur la violence et la guerre, quand aujourd’hui dans notre pays le riches se font la guerre, ce sont le pauvres qui meurent, ce vraix que la guerre, on ne la fait pas: mais c’est elle qui nous fait le pauvre. La violence et la guerre qui m’a fait aimé la philosophie de J.P SARTRE.

RÉPONDRE Mike 13/08/2018 à 15:24 “l’angoisse est le vertige de la liberté” est une citation de Soren Kierkegaard, me semble t-il.

RÉPONDRE Laisser un commentaire Votre adresse de messagerie ne sera pas publiée. Les champs obligatoires sont indiqués avec *

Commentaire

Nom * Adresse de messagerie * Site web La modération des commentaires est activée. Votre commentaire peut prendre un certain temps avant d’apparaître.

ARTICLES LES + LUS

Bac Philo Exemple de Dissertation Philosophique

Recherches Les Films Philosophiques

Bac Philo Bac Philosophie 2020 : Notre guide des révisions new york coronavirus Recherches Pandémie : Est-ce venu l’ère du technicisme ? Macron, un président en guerre contre le coronavirus Recherches Propos sur la guerre, ou la fabrique d’une illusion – Tribune

Philosophes Courants de la philosophie QUIZ PHILO quiz philo L’APP LA-PHILOSOPHIE.COM Application Philosophie Téléchargez notre application gratuite sur le Play Store

DERNIERS ARTICLES Les Films Philosophiques Que nous apprend l’expérience du virus ? Une approche philosophique de la maladie La Neuro-philosophie et le Transhumanisme Créon, héros tragique: Une lecture philosophique du mythe grec La philosophie de Heidegger: De l’étant à l’Etre More Stories

Recherches Le culte de la performance comme mode d’existence ? Plan du site Publicité / Contact QUI SOMMES-NOUS? Depuis 2008, la-philosophie.com agit pour la diffusion de la tradition et des grandes pensées philosophiques. Indépendant, le site est maintenu par une équipe d'anciens étudiants en sciences humaines, aujourd'hui professeurs ou journalistes. Les colonnes du site sont ouvertes aux contributions externes. Julien Josset, fondateur du site. La-Philosophie.com en bref La-Philosophie.com aide les élèves de terminales dans la préparation du bac, les élèves de classes prépa dans celle de leur concours, ceux de fac dans leurs recherches, et enfin tous les curieux de sciences humaines à étancher leur soif de savoir.

Le site couvre ainsi les grandes traditions philosophiques, des présocratiques aux philosophes contemporains, tout en essayant d’apporter une lecture philosophique au champ culturel en général, qu’il s’agisse de cinéma, de littérature, de politique ou de musique.

Qu’est-ce que la philosophie*? Etymologiquement, philosophie signifie amour de la sagesse. Avant d’être une discipline d’étude, il s’agit avant tout d’une certaine manière de voir le monde, de le questionner. Le principe fondateur de la philosophie est sans doute ainsi l’étonnement, qui provoque et suscite le questionnement. Ensuite, philosopher consiste à argumenter de manière rationnelle sur son étonnement.

• Nous avons publié plus de 700 articles, tous cherchant directement ou indirectement à répondre à cette question. Sachez avant tout qu’il n’existe pas de réponse unique à cette question.

PRINCIPAUX PHILOSOPHES Socrate, Platon, Aristote, Epicure, Descartes, Machiavel, Spinoza, Hobbes, Rousseau, Montesquieu, Kant, Schopenhauer, Hegel, Nietzsche, Marx, Freud, Sartre, Heidegger PARTENAIRES Cours de Droit La Filosofia (en espagnol) Philosophie Sorbonne The-Philosophy.com (en anglais) PROPULSÉ PAR WORDPRESS - LA-PHILOSOPHIE.COM - 2008-2020 MODIFIER LES PARAMÈTRES DE CONFIDENTIALITÉ

View Details

Auteurs français, Citations CITATIONS DE SARTRE Jean-Paul Sartre, existentialisme

Les citations philosophiques de Jean-Paul Sartre Table des Matières [Cacher]

1 Les citations philosophiques de Jean-Paul Sartre 2 Sartre et l’existence : 3 Sartre et la liberté : 4 Sartre et la conscience : 5 Sartre et autrui : 6 Sartre et le corps : 7 Sartre et l’amour : 8 Sartre, la violence et la guerre : 9 Sartre, Dieu et l’athéisme : 9.1 Voir les articles sur Sartre : 9.2 Tous les articles sur Sartre 9.3 La philosophie de Sartre 9.4 La morale de Sartre 9.5 L’existentialisme est un humanisme de Sartre 9.6 L’existence précède l’essence 9.7 La mauvaise foi dans l’oeuvre de Sartre 9.8 Analyse de la Nausée 9.9 L’Etre et le Néant Jean-Paul Sartre est le philosophe français le plus lu et le plus commenté dans le monde. Fondateur de l’existentialisme, son œuvre prend pied chez Kierkegaard, Heidegger et Husserl principalement.

Auteur de théâtre, de roman et de manifestes politiques, la diversité de son œuvre, alliée à l’aridité de sa terminologie, rendent sa philosophie complexe à appréhender. Voici quelques citations pour saisir l’essentiel de sa philosophie : [ad#ad-5]

Sartre et l’existence : – “L’existence précède l’essence“

– “On meurt toujours trop tôt – ou trop tard. Et cependant la vie est là, terminée. Tu n’es rien d’autre que ta vie”

– “Qu’est-ce qu’exister ? Se boire sans soif”

– “L’existence précède l’essence. Cela signifie que l’homme existe d’abord, se rencontre, surgit dans le monde, et qu’il se définit ensuite”

Sartre et la liberté : – “L’homme est condamné à être libre“

– “L’angoisse est le vertige de la liberté”

– “Seuls les actes décident de ce qu’on a voulu”

– “On peut toujours faire quelque chose de ce qu’on a fait de nous”

– “Ne pas choisir, c’est encore choisir”

– “L’homme n’est rien d’autre que ce qu’il se fait”

– “Choix et conscience sont une seule et même chose”

– “Chaque homme doit inventer son chemin”

– “En fait, nous sommes une liberté qui choisit, mais nous ne choisissons pas d’être libres : nous sommes condamnés à la liberté”

– “Je construis l’universel en me choisissant; je le construis en comprenant le projet de tout autre homme, de quelque époque qu’il soit”

– “Etre condamné à être libre, cela signifie qu’on ne saurait trouver à ma liberté d’autres limites qu’elle-même”

– “C’est dans l’échec que l’on doit agir”

– “Agir, c’est modifier la figure du monde”

Sartre et la conscience : – “Etre une conscience c’est s’éclater vers le monde”

– “La conscience se constitue elle-même en même temps qu’elle se constitue comme conscience de l’autre”

– “La conscience est en réalité une conscience de conscience, car pour être conscience du monde; la conscience doit aussi être conscience d’elle-même”

Sartre et autrui : – “Alors, c’est ça l’enfer. Je n’aurais jamais cru… Vous vous rappelez: le soufre, le bûcher, le gril… Ah! quelle plaisanterie. Pas besoin de gril : l’enfer, c’est les Autres”

– “Autrui, c’est ce moi qui n’est pas moi”

– “Je ne constitue pas autrui, je le rencontre”

– “Ma chute originelle, c’est l’existence d’autrui”

– “Le conflit est le sens originel du Pour-Autrui”

– “Ainsi, autrui est d’abord pour moi l’être pour qui je suis objet”

– “Ma chute originelle, c’est l’existence de l’autre”

– “On me voit donc je suis”

– “Le Pour-Soi est toujours aussi un Pour-Autrui”

– “Il n’y a d’oppression que d’une liberté par une liberté”

– “Un homme peut toujours faire quelque chose de ce qu’on a fait de lui”

Sartre et le corps : – “Le corps n’est pas uni à la conscience, il est tout entier psychique”

– “Le corps est un Pour-Soi, et non un En-Soi dans le Pour-Soi”

– “La conscience existe dans son corps”

Sartre et l’amour : – “Aimer est, dans son essence, le projet de se faire aimer”

– “Un amour, une carrière, une révolution : autant d’entreprises que l’on commence en ignorant leur issue”

– “C’est là le fond de la joie d’amour, lorsqu’elle existe: nous sentir justifiés d’exister”

– “Aimer est le projet de se faire aimer”

– “L’idéal de l’entreprise amoureuse est la liberté aliénée : chacun veut que la liberté de l’autre s’aliène”

– “Ma tentative originelle pour me saisir de la subjectivité libre de l’autre à travers son objectité pour moi est le désir sexuel”

– “L’être qui désire, c’est la conscience se faisant corps”

– “Le désir s’exprime par la caresse comme la pensée par le langage”

– “Le plaisir est la mort et l’échec du désir”

– “La maternité est la possibilité ontologique de la fraternité”

Sartre, la violence et la guerre : – “La violence n’est pas un moyen parmi d’autres d’atteindre la fin, mais le choix délibéré d’atteindre la fin par n’importe quel moyen”

– “A moitié victime, à moitié complice, comme tout le monde”

– “La guerre, on ne la fait pas : c’est elle qui nous fait”

– “Quand les riches se font la guerre, ce sont les pauvres qui meurent”

Sartre, Dieu et l’athéisme : – “Dieu est mort, mais l’homme n’est pas, pour autant, devenu athée. Ce silence du transcendant, joint à la permanence du besoin religieux chez l’homme moderne, voilà la grande affaire aujourd’hui comme hier”

– “L’absence de Dieu n’est pas la fermeture, c’est ouverture sur l’infini”

– “Dieu, c’est la solitude des hommes… Si Dieu existe, l’homme est néant”

Voir les articles sur Sartre : Tous les articles sur Sartre La philosophie de Sartre La morale de Sartre L’existentialisme est un humanisme de Sartre L’existence précède l’essence La mauvaise foi dans l’oeuvre de Sartre Analyse de la Nausée L’Etre et le Néant 21 Facebook Twitter Pinterest GOOGLE + LINKEDIN EMAIL You may also like 21 Comments GODIN 01/02/2011 à 18:31 Je m’intéresse beaucoup à la philosophie où pouurais-je commander des livres.

Merci

Danielle GODIN

RÉPONDRE philocours 02/02/2011 à 14:40 Bonjour Danielle,

je vous recommande le site abebooks.fr, très sérieux.

L’équipe La-Philosophie.com

RÉPONDRE gontrand 18/02/2011 à 12:59 j’adore les citations de Jean-Paul Sartre, le plus grands philosophe français ! il a tout compris sur la liberté, la métaphysique et la condition humaine. l’existentialisme est un humanisme m’a fait aimé la philosophie

RÉPONDRE dana 04/12/2011 à 11:23 Sartre s’est un grand philosophe

RÉPONDRE dana 04/12/2011 à 11:23 Sartre c’est un grand philosophe

RÉPONDRE Ping : Sartre : L’existentialisme est un humanisme (commentaire et résumé) Ping : La morale de Sartre Ping : Sartre et la liberté Ping : Sartre : L'enfer, c'est les autres Rudolf Daniel 17/04/2013 à 12:57 L’un des plus grands philosophes de l’histoire. Sartre, tu manques à l’humanité!

RÉPONDRE taylor 31/10/2013 à 12:42 l’homme est sa sagesse s’epanoui

RÉPONDRE LOCO 27/02/2014 à 02:28 “On me voit, donc je suis” Sartre Ce n’est pas vrai puisque tout ce qu’on voit et même tout ce qu’on expérimente n’est plus, c’est le passé, c’était. Alors “On me voit, donc j’étais” Je ne suis que dans ma conscience. J’ai conscience d’être mais je ne peux pas l’expérimenter. Expérience et conscience ne sont pas la même chose.

RÉPONDRE diabate 22/11/2014 à 21:18 je ve us avoir plus

RÉPONDRE Pauly 11/12/2015 à 09:28 Sartre c’est un grand Philosophe.

RÉPONDRE Christian Martial Poos 27/03/2016 à 22:44 De l’existentialisme à Autrui,en passant par le Néant et …Il ya que l’Etre diversifie les termes ,pour arriver à expliquer la marche du monde sans totalement se nier ,je veux dire ,réfuter qu’il est là pour obeir à sa progression dont il ignore l’issue

RÉPONDRE KOUIDER MAROUF 10/07/2016 à 15:00 conciliation du sujet et de l’objet:on ne peut parler de l’islamophobie uniquement si on est islamophobe ,aurait dit surement SARTRE.M

RÉPONDRE KOUIDER MAROUF 10/07/2016 à 15:08 conciliation du sjet et de l’objet:on ne peut parlerde l’islamophobie quand n’etant islamophobe ,aurait certainement dit jpSARTRE?le seul et unque philosophe(la presse française est marante quand elle glorifie un criminel de guerre BHL et le cite à tout bout de champs comme philosophe)qu elle arrete pour l’amour de la paix et la justice cette mascarade!avec toutes les tartres qu il a reçu sur la gueule….

RÉPONDRE Anonyme 11/09/2016 à 17:21 La philosophie de satre me donne toujour l’amour de vivre e de pouvoir atteindre mes fins car il dit: l’hom n’est rien d ce qu’il se fait . Sans Sartre la vie serai com 1mond sans âme me lov sartr

RÉPONDRE Anonyme 02/10/2016 à 20:34 homme comme d autres

RÉPONDRE Christian Bienvenu 15/12/2017 à 17:08 Je m’intéresse beaucoup à la philosophie de J.P SARTRE le plus grand philosophe français: car il a bien compris sur la violence et la guerre, quand aujourd’hui dans notre pays le riches se font la guerre, ce sont le pauvres qui meurent, ce vraix que la guerre, on ne la fait pas: mais c’est elle qui nous fait le pauvre. La violence et la guerre qui m’a fait aimé la philosophie de J.P SARTRE.

RÉPONDRE Mike 13/08/2018 à 15:24 “l’angoisse est le vertige de la liberté” est une citation de Soren Kierkegaard, me semble t-il.

RÉPONDRE Laisser un commentaire Votre adresse de messagerie ne sera pas publiée. Les champs obligatoires sont indiqués avec *

Commentaire

Nom * Adresse de messagerie * Site web La modération des commentaires est activée. Votre commentaire peut prendre un certain temps avant d’apparaître.

ARTICLES LES + LUS

Bac Philo Exemple de Dissertation Philosophique

Recherches Les Films Philosophiques

Bac Philo Bac Philosophie 2020 : Notre guide des révisions new york coronavirus Recherches Pandémie : Est-ce venu l’ère du technicisme ? Macron, un président en guerre contre le coronavirus Recherches Propos sur la guerre, ou la fabrique d’une illusion – Tribune

Philosophes Courants de la philosophie QUIZ PHILO quiz philo L’APP LA-PHILOSOPHIE.COM Application Philosophie Téléchargez notre application gratuite sur le Play Store

DERNIERS ARTICLES Les Films Philosophiques Que nous apprend l’expérience du virus ? Une approche philosophique de la maladie La Neuro-philosophie et le Transhumanisme Créon, héros tragique: Une lecture philosophique du mythe grec La philosophie de Heidegger: De l’étant à l’Etre More Stories

Recherches Le culte de la performance comme mode d’existence ? Plan du site Publicité / Contact QUI SOMMES-NOUS? Depuis 2008, la-philosophie.com agit pour la diffusion de la tradition et des grandes pensées philosophiques. Indépendant, le site est maintenu par une équipe d'anciens étudiants en sciences humaines, aujourd'hui professeurs ou journalistes. Les colonnes du site sont ouvertes aux contributions externes. Julien Josset, fondateur du site. La-Philosophie.com en bref La-Philosophie.com aide les élèves de terminales dans la préparation du bac, les élèves de classes prépa dans celle de leur concours, ceux de fac dans leurs recherches, et enfin tous les curieux de sciences humaines à étancher leur soif de savoir.

Le site couvre ainsi les grandes traditions philosophiques, des présocratiques aux philosophes contemporains, tout en essayant d’apporter une lecture philosophique au champ culturel en général, qu’il s’agisse de cinéma, de littérature, de politique ou de musique.

Qu’est-ce que la philosophie*? Etymologiquement, philosophie signifie amour de la sagesse. Avant d’être une discipline d’étude, il s’agit avant tout d’une certaine manière de voir le monde, de le questionner. Le principe fondateur de la philosophie est sans doute ainsi l’étonnement, qui provoque et suscite le questionnement. Ensuite, philosopher consiste à argumenter de manière rationnelle sur son étonnement.

• Nous avons publié plus de 700 articles, tous cherchant directement ou indirectement à répondre à cette question. Sachez avant tout qu’il n’existe pas de réponse unique à cette question.

PRINCIPAUX PHILOSOPHES Socrate, Platon, Aristote, Epicure, Descartes, Machiavel, Spinoza, Hobbes, Rousseau, Montesquieu, Kant, Schopenhauer, Hegel, Nietzsche, Marx, Freud, Sartre, Heidegger PARTENAIRES Cours de Droit La Filosofia (en espagnol) Philosophie Sorbonne The-Philosophy.com (en anglais) PROPULSÉ PAR WORDPRESS - LA-PHILOSOPHIE.COM - 2008-2020 MODIFIER LES PARAMÈTRES DE CONFIDENTIALITÉ

View Details

Jean-Paul Charles Aymard Sartre (/?s??rtr?/, US also /?s??rt/;[8] French: [sa?t?]; 21 June 1905 – 15 April 1980) was a French philosopher, playwright, novelist, screenwriter, political activist, biographer, and literary critic. He was one of the key figures in the philosophy of existentialism and phenomenology, and one of the leading figures in 20th-century French philosophy and Marxism. His work has also influenced sociology, critical theory, post-colonial theory, and literary studies, and continues to influence these disciplines.

Sartre was also noted for his open relationship with prominent feminist and fellow existentialist philosopher and writer Simone de Beauvoir. Together, Sartre and de Beauvoir challenged the cultural and social assumptions and expectations of their upbringings, which they considered bourgeois, in both lifestyle and thought. The conflict between oppressive, spiritually destructive conformity (mauvaise foi, literally, "bad faith") and an "authentic" way of "being" became the dominant theme of Sartre's early work, a theme embodied in his principal philosophical work Being and Nothingness (L'Être et le Néant, 1943).[9] Sartre's introduction to his philosophy is his work Existentialism Is a Humanism (L'existentialisme est un humanisme, 1946), originally presented as a lecture.

He was awarded the 1964 Nobel Prize in Literature despite attempting to refuse it, saying that he always declined official honours and that "a writer should not allow himself to be turned into an institution".[10]

Contents 1 Biography 1.1 Early life 1.2 World War II 1.3 Cold War politics and anticolonialism 1.4 Late life and death 2 Thought 3 Career as public intellectual 4 Literature 5 Criticism 6 Works 7 See also 8 References 9 Sources 10 Further reading 11 External links 11.1 By Sartre 11.2 On Sartre Biography Early life Jean-Paul Sartre was born on 21 June 1905 in Paris as the only child of Jean-Baptiste Sartre, an officer of the French Navy, and Anne-Marie (Schweitzer).[11] His mother was of Alsatian origin and the first cousin of Nobel Prize laureate Albert Schweitzer, whose father Louis Théophile was the younger brother of Anne-Marie's father.[12] When Sartre was two years old, his father died of an illness, which he most likely contracted in Indochina. Anne-Marie moved back to her parents' house in Meudon, where she raised Sartre with help from her father Charles Schweitzer, a teacher of German who taught Sartre mathematics and introduced him to classical literature at a very early age.[13] When he was twelve, Sartre's mother remarried, and the family moved to La Rochelle, where he was frequently bullied.[14]

As a teenager in the 1920s, Sartre became attracted to philosophy upon reading Henri Bergson's essay Time and Free Will: An Essay on the Immediate Data of Consciousness.[15] He attended the Cours Hattemer, a private school in Paris.[16] He studied and earned certificates in psychology, history of philosophy, logic, general philosophy, ethics and sociology, and physics, as well as his diplôme d'études supérieures [fr] (roughly equivalent to an MA thesis) in Paris at the École Normale Supérieure, an institution of higher education that was the alma mater for several prominent French thinkers and intellectuals.[2] (His 1928 MA thesis under the title "L'Image dans la vie psychologique: rôle et nature" ["Image in Psychological Life: Role and Nature"] was supervised by Henri Delacroix.)[2] It was at ENS that Sartre began his lifelong, sometimes fractious, friendship with Raymond Aron.[17] Perhaps the most decisive influence on Sartre's philosophical development was his weekly attendance at Alexandre Kojève's seminars, which continued for a number of years.[18]

From his first years in the École Normale, Sartre was one of its fiercest pranksters.[19][20] In 1927, his antimilitarist satirical cartoon in the revue of the school, coauthored with Georges Canguilhem, particularly upset the director Gustave Lanson.[21] In the same year, with his comrades Nizan, Larroutis, Baillou and Herland,[22] he organized a media prank following Charles Lindbergh's successful New York City–Paris flight; Sartre & Co. called newspapers and informed them that Lindbergh was going to be awarded an honorary École degree. Many newspapers, including Le Petit Parisien, announced the event on 25 May. Thousands, including journalists and curious spectators, showed up, unaware that what they were witnessing was a stunt involving a Lindbergh look-alike.[21][23][24] The public's resultant outcry[need quotation to verify] forced Lanson to resign.[21][25]

In 1929 at the École Normale, he met Simone de Beauvoir, who studied at the Sorbonne and later went on to become a noted philosopher, writer, and feminist. The two became inseparable and lifelong companions, initiating a romantic relationship,[26] though they were not monogamous.[27] The first time Sartre took the agrégation, he failed. He took it a second time and virtually tied for first place with Beauvoir, although Sartre was eventually awarded first place, with Beauvoir second.[28][29]

Sartre was drafted into the French Army from 1939 to 1941 and served as a meteorologist for some time.[30] He later argued in 1959 that each French person was responsible for the collective crimes during the Algerian War of Independence.[31]

From 1931 until 1945, Sartre taught at various lycées of Le Havre (at the Lycée de Le Havre, the present-day Lycée François-Ier (Le Havre) [fr], 1931–36), Laon (at the Lycée de Laon, 1936–37), and, finally, Paris (at the Lycée Pasteur, 1937–39, and at the Lycée Condorcet, 1941–44;[32] see below).

In 1932, Sartre discovered Voyage au bout de la nuit by Louis-Ferdinand Céline, a book that had a remarkable influence on him.[33]

In 1933–34, he succeeded Raymond Aron at the Institut français d'Allemagne in Berlin where he studied Edmund Husserl's phenomenological philosophy. Aron had already advised him in 1930 to read Emmanuel Levinas's Théorie de l'intuition dans la phénoménologie de Husserl (The Theory of Intuition in Husserl's Phenomenology).[34]

The Neo-Hegelian revival led by Alexandre Kojève and Jean Hyppolite in the 1930s inspired a whole generation of French thinkers, including Sartre, to discover Hegel's Phenomenology of Spirit.[35]

World War II In 1939 Sartre was drafted into the French army, where he served as a meteorologist.[36] He was captured by German troops in 1940 in Padoux,[37] and he spent nine months as a prisoner of war—in Nancy and finally in Stalag XIII-D, Trier, where he wrote his first theatrical piece, Barionà, fils du tonnerre, a drama concerning Christmas. It was during this period of confinement that Sartre read Martin Heidegger's Sein und Zeit, later to become a major influence on his own essay on phenomenological ontology. Because of poor health (he claimed that his poor eyesight and exotropia affected his balance) Sartre was released in April 1941. According to other sources, he escaped after a medical visit to the ophthalmologist.[38] Given civilian status, he recovered his teaching position at Lycée Pasteur near Paris and settled at the Hotel Mistral. In October 1941 he was given a position, previously held by a Jewish teacher who had been forbidden to teach by Vichy law, at Lycée Condorcet in Paris.

Sartre (third from left) and other French journalists visit General George C. Marshall in the Pentagon, 1945 After coming back to Paris in May 1941, he participated in the founding of the underground group Socialisme et Liberté ("Socialism and Liberty") with other writers Simone de Beauvoir, Maurice Merleau-Ponty, Jean-Toussaint Desanti, Dominique Desanti, Jean Kanapa, and École Normale students. In spring of 1941, Sartre suggested with "cheerful ferocity" at a meeting that the Socialisme et Liberté assassinate prominent war collaborators like Marcel Déat, but de Beauvoir noted his idea was rejected as "none of us felt qualified to make bombs or hurl grenades".[39] The British historian Ian Ousby observed that the French always had far more hatred for collaborators than they did for the Germans, noting it was French people like Déat that Sartre wanted to assassinate rather than the military governor of France, General Otto von Stülpnagel, and the popular slogan always was "Death to Laval!" rather than "Death to Hitler!".[40] In August Sartre and de Beauvoir went to the French Riviera seeking the support of André Gide and André Malraux. However, both Gide and Malraux were undecided, and this may have been the cause of Sartre's disappointment and discouragement. Socialisme et liberté soon dissolved and Sartre decided to write instead of being involved in active resistance. He then wrote Being and Nothingness, The Flies, and No Exit, none of which were censored by the Germans, and also contributed to both legal and illegal literary magazines.

In his essay "Paris under the Occupation", Sartre wrote that the "correct" behaviour of the Germans had entrapped too many Parisians into complicity with the occupation, accepting what was unnatural as natural:

The Germans did not stride, revolver in hand, through the streets. They did not force civilians to make way for them on the pavement. They would offer seats to old ladies on the Metro. They showed great fondness for children and would pat them on the cheek. They had been told to behave correctly and being well-disciplined, they tried shyly and conscientiously to do so. Some of them even displayed a naive kindness which could find no practical expression.[41]

Sartre noted when Wehrmacht soldiers asked Parisians politely in their German-accented French for directions, people usually felt embarrassed and ashamed as they tried their best to help out the Wehrmacht which led Sartre to remark "We could not be natural".[42] French was a language widely taught in German schools and most Germans could speak at least some French. Sartre himself always found it difficult when a Wehrmacht soldier asked him for directions, usually saying he did not know where it was that the soldier wanted to go, but still felt uncomfortable as the very act of speaking to the Wehrmacht meant he had been complicit in the Occupation.[43] Ousby wrote: "But, in however humble a fashion, everyone still had to decide how they were going to cope with life in a fragmenting society ... So Sartre's worries ... about how to react when a German soldier stopped him in the street and asked politely for directions were not as fussily inconsequential as they might sound at first. They were emblematic of how the dilemmas of the Occupation presented themselves in daily life".[43] Sartre wrote the very "correctness" of the Germans caused moral corruption in many people who used the "correct" behavior of the Germans as an excuse for passivity, and the very act of simply trying to live one's day-to-day existence without challenging the occupation aided the "New Order in Europe", which depended upon the passivity of ordinary people to accomplish its goals.[41]

Throughout the occupation, it was German policy to plunder France and food shortages were always a major problem as the majority of food from the French countryside went to Germany.[44] Sartre wrote about the "languid existence" of the Parisians as people waited obsessively for the one weekly arrival of trucks bringing food from the countryside that the Germans allowed, writing: "Paris would grow peaked and yawn with hunger under the empty sky. Cut off from the rest of the world, fed only through the pity or some ulterior motive, the town led a purely abstract and symbolic life".[44] Sartre himself lived on a diet of rabbits sent to him by a friend of de Beauvoir living in Anjou.[45] The rabbits were usually in an advanced state of decay full of maggots, and despite being hungry, Sartre once threw out one rabbit as uneatable, saying it had more maggots in it than meat.[45] Sartre also remarked that conversations at the Café de Flore between intellectuals had changed, as the fear that one of them might be a mouche (informer) or a writer of the corbeau (anonymous denunciatory letters) meant that no one really said what they meant anymore, imposing self-censorship.[46] Sartre and his friends at the Café de Flore had reasons for their fear; by September 1940, the Abwehr alone had already recruited 32,000 French people to work as mouches while by 1942 the Paris Kommandantur was receiving an average of 1,500 letters/per day sent by the corbeaux.[47]

Sartre wrote under the occupation Paris had become a "sham", resembling the empty wine bottles displayed in shop windows as all of the wine had been exported to Germany, looking like the old Paris, but hollowed out, as what had made Paris special was gone.[48] Paris had almost no cars on the streets during the occupation as the oil went to Germany while the Germans imposed a nightly curfew, which led Sartre to remark that Paris "was peopled by the absent".[49] Sartre also noted that people began to disappear under the occupation, writing:

One day you might phone a friend and the phone would ring for a long time in an empty flat. You would go round and ring the doorbell, but no-one would answer it. If the concierge forced the door, you would find two chairs standing close together in the hall with the fag-ends of German cigarettes on the floor between their legs. If the wife or mother of the man who had vanished had been present at his arrest, she would tell you that he had been taken away by very polite Germans, like those who asked the way in the street. And when she went to ask what had happened to them at the offices in the Avenue Foch or the Rue des Saussaies she would be politely received and sent away with comforting words" [No. 11 Rue des Saussaies was the headquarters of the Gestapo in Paris].[50]

Sartre wrote the feldgrau ("field grey") uniforms of the Wehrmacht and the green uniforms of the Order Police which had seemed so alien in 1940 had become accepted, as people were numbed into accepting what Sartre called "a pale, dull green, unobtrusive strain, which the eye almost expected to find among the dark clothes of the civilians".[51] Under the occupation, the French often called the Germans les autres ("the others"), which inspired Sartre's aphorism in his play Huis clos ("No Exit") of "l'enfer, c'est les Autres" ("Hell is other people").[52] Sartre intended the line "l'enfer, c'est les Autres" at least in part to be a dig at the German occupiers.[52]

After August 1944 and the Liberation of Paris, he wrote Anti-Semite and Jew. In the book he tries to explain the etiology of "hate" by analyzing antisemitic hate. Sartre was a very active contributor to Combat, a newspaper created during the clandestine period by Albert Camus, a philosopher and author who held similar beliefs. Sartre and de Beauvoir remained friends with Camus until 1951, with the publication of Camus's The Rebel. Later, while Sartre was labeled by some authors as a resistant, the French philosopher and resistant Vladimir Jankelevitch criticized Sartre's lack of political commitment during the German occupation, and interpreted his further struggles for liberty as an attempt to redeem himself. According to Camus, Sartre was a writer who resisted; not a resister who wrote.

In 1945, after the war ended, Sartre moved to an apartment on the rue Bonaparte which was where he was to produce most of his subsequent work, and where he lived until 1962. It was from there that he helped establish a quarterly literary and political review, Les Temps modernes (Modern Times), in part to popularize his thought.[53] He ceased teaching and devoted his time to writing and political activism. He would draw on his war experiences for his great trilogy of novels, Les Chemins de la Liberté (The Roads to Freedom) (1945–1949).

Cold War politics and anticolonialism

Jean-Paul Sartre (middle) and Simone de Beauvoir (left) meeting with Che Guevara (right) in Cuba, 1960 The first period of Sartre's career, defined in large part by Being and Nothingness (1943), gave way to a second period—when the world was perceived as split into communist and capitalist blocs—of highly publicized political involvement. Sartre tended to glorify the Resistance after the war as the uncompromising expression of morality in action, and recalled that the résistants were a "band of brothers" who had enjoyed "real freedom" in a way that did not exist before nor after the war.[54] Sartre was "merciless" in attacking anyone who had collaborated or remained passive during the German occupation; for instance, criticizing Camus for signing an appeal to spare the collaborationist writer Robert Brasillach from being executed.[54] His 1948 play Les mains sales (Dirty Hands) in particular explored the problem of being a politically "engaged" intellectual. He embraced Marxism but did not join the Communist Party. For a time in the late 1940s, Sartre described French nationalism as "provincial" and in a 1949 essay called for a "United States of Europe".[55] In an essay published in the June 1949 edition of the journal Politique étrangère, Sartre wrote:

If we want French civilization to survive, it must be fitted into the framework of a great European civilization. Why? I have said that civilization is the reflection on a shared situation. In Italy, in France, in Benelux, in Sweden, in Norway, in Germany, in Greece, in Austria, everywhere we find the same problems and the same dangers ... But this cultural polity has prospects only as elements of a policy which defends Europe's cultural autonomy vis-à-vis America and the Soviet Union, but also its political and economic autonomy, with the aim of making Europe a single force between the blocs, not a third bloc, but an autonomous force which will refuse to allow itself to be torn into shreds between American optimism and Russian scientificism.[56]

About the Korean War, Sartre wrote: "I have no doubt that the South Korean feudalists and the American imperialists have promoted this war. But I do not doubt either that it was begun by the North Koreans".[57] In July 1950, Sartre wrote in Les Temps Modernes about his and de Beauvoir's attitude to the Soviet Union:

As we were neither members of the [Communist] party nor its avowed sympathizers, it was not our duty to write about Soviet labor camps; we were free to remain aloof from the quarrel over the nature of this system, provided that no events of sociological significance had occurred.[58]

Sartre held that the Soviet Union was a "revolutionary" state working for the betterment of humanity and could be criticized only for failing to live up to its own ideals, but that critics had to take in mind that the Soviet state needed to defend itself against a hostile world; by contrast Sartre held that the failures of "bourgeois" states were due to their innate shortcomings.[54] The Swiss journalist François Bondy wrote that, based on a reading of Sartre's numerous essays, speeches and interviews "a simple basic pattern never fails to emerge: social change must be comprehensive and revolutionary" and the parties that promote the revolutionary charges "may be criticized, but only by those who completely identify themselves with its purpose, its struggle and its road to power", deeming Sartre's position to be "existentialist".[54]

While a Marxist, Sartre attacked what he saw as abuses of freedom and human rights by the Soviet Union. In 1954, Sartre visited the Soviet Union, which he stated he found a "complete freedom of criticism" while condemning the United States for sinking into "prefascism".[59] Sartre wrote about those Soviet writers expelled from the Soviet Writers' Union "still had the opportunity of rehabilitating themselves by writing better books".[60] He was one of the first French journalists to expose the existence of the labor camps, and vehemently opposed the invasion of Hungary, Russian anti-Semitism, and the execution of dissidents.[citation needed] About the Hungarian revolt of 1956, Sartre wrote: "In spite of everything, the Rakosi regime stood for socialization. Only it did it badly and that is worse than not to do so at all".[61] Sartre came to admire the Polish leader W?adys?aw Gomu?ka, a man who favored a "Polish road to socialism" and wanted more independence for Poland, but was loyal to the Soviet Union because of the Oder-Neisse line issue.[62] Sartre's newspaper Les Temps Modernes devoted a number of special issues in 1957 and 1958 to Poland under Gomu?ka, praising him for his reforms.[62] Bondy wrote of the notable contradiction between Sarte's "ultra Bolshevism" as he expressed admiration for the Chinese leader Mao Zedong as the man who led the oppressed masses of the Third World into revolution while also praising more moderate Communist leaders like Gomu?ka.[62]

As an anti-colonialist, Sartre took a prominent role in the struggle against French rule in Algeria, and the use of torture and concentration camps by the French in Algeria. He became an eminent supporter of the FLN in the Algerian War and was one of the signatories of the Manifeste des 121. Consequently, Sartre became a domestic target of the paramilitary Organisation armée secrète (OAS), escaping two bomb attacks in the early '60s.[63] (He had an Algerian mistress, Arlette Elkaïm, who became his adopted daughter in 1965.) He opposed U.S. involvement in the Vietnam War and, along with Bertrand Russell and others, organized a tribunal intended to expose U.S. war crimes, which became known as the Russell Tribunal in 1967.

Sketch of Sartre for the New York Times by Reginald Gray, 1965 His work after Stalin's death, the Critique de la raison dialectique (Critique of Dialectical Reason), appeared in 1960 (a second volume appearing posthumously). In the Critique Sartre set out to give Marxism a more vigorous intellectual defense than it had received until then; he ended by concluding that Marx's notion of "class" as an objective entity was fallacious. Sartre's emphasis on the humanist values in the early works of Marx led to a dispute with a leading leftist intellectual in France in the 1960s, Louis Althusser, who claimed that the ideas of the young Marx were decisively superseded by the "scientific" system of the later Marx. In the late 1950s, Sartre began to argue that the European working classes were too apolitical to carry out the revolution predicated by Marx, and influenced by Frantz Fanon stated to argue it was the impoverished masses of the Third World, the "real damned of the earth", who would carry out the revolution.[64] A major theme of Sarte's political essays in the 1960s was of his disgust with the "Americanization" of the French working class who would much rather watch American TV shows dubbed into French than agitate for a revolution.[54]

Sartre went to Cuba in the 1960s to meet Fidel Castro and spoke with Ernesto "Che" Guevara. After Guevara's death, Sartre would declare him to be "not only an intellectual but also the most complete human being of our age"[65] and the "era's most perfect man".[66] Sartre would also compliment Guevara by professing that "he lived his words, spoke his own actions and his story and the story of the world ran parallel".[67] However he stood against the persecution of gays by Castro's régime, which he compared to Nazi persecution of the Jews, and said: "In Cuba there are no Jews, but there are homosexuals".[68]

During a collective hunger strike in 1974, Sartre visited Red Army Faction member Andreas Baader in Stammheim Prison and criticized the harsh conditions of imprisonment.[69]

Towards the end of his life, Sartre began to describe himself as a "special kind" of anarchist.[70]

Late life and death

Hélène de Beauvoir's house in Goxwiller, where Sartre tried to hide from the media after being awarded the Nobel Prize. In 1964 Sartre renounced literature in a witty and sardonic account of the first ten years of his life, Les Mots (The Words). The book is an ironic counterblast to Marcel Proust, whose reputation had unexpectedly eclipsed that of André Gide (who had provided the model of littérature engagée for Sartre's generation). Literature, Sartre concluded, functioned ultimately as a bourgeois substitute for real commitment in the world. In October 1964, Sartre was awarded the Nobel Prize in Literature but he declined it. He was the first Nobel laureate to voluntarily decline the prize,[71] and remains one of only two laureates to do so.[72] According to Lars Gyllensten, in the book Minnen, bara minnen ("Memories, Only Memories") published in 2000, Sartre himself or someone close to him got in touch with the Swedish Academy in 1975 with a request for the prize money, but was refused.[73] In 1945, he had refused the Légion d'honneur.[74] The Nobel prize was announced on 22 October 1964; on 14 October, Sartre had written a letter to the Nobel Institute, asking to be removed from the list of nominees, and warning that he would not accept the prize if awarded, but the letter went unread;[75] on 23 October, Le Figaro published a statement by Sartre explaining his refusal. He said he did not wish to be "transformed" by such an award, and did not want to take sides in an East vs. West cultural struggle by accepting an award from a prominent Western cultural institution.[75] Nevertheless, he was that year's prizewinner.[76] After being awarded the prize he tried to escape the media by hiding in the house of Simone's sister Hélène de Beauvoir in Goxwiller, Alsace.[citation needed]

Jean-Paul Sartre in Venice in 1967 Though his name was then a household word (as was "existentialism" during the tumultuous 1960s), Sartre remained a simple man with few possessions, actively committed to causes until the end of his life, such as the May 1968 strikes in Paris during the summer of 1968 during which he was arrested for civil disobedience. President Charles de Gaulle intervened and pardoned him, commenting that "you don't arrest Voltaire".[77]

Sartre's and de Beauvoir's grave in the cimetière du Montparnasse. In 1975, when asked how he would like to be remembered, Sartre replied:

I would like [people] to remember Nausea, [my plays] No Exit and The Devil and the Good Lord, and then my two philosophical works, more particularly the second one, Critique of Dialectical Reason. Then my essay on Genet, Saint Genet. ... If these are remembered, that would be quite an achievement, and I don't ask for more. As a man, if a certain Jean-Paul Sartre is remembered, I would like people to remember the milieu or historical situation in which I lived, ... how I lived in it, in terms of all the aspirations which I tried to gather up within myself.[78]

Sartre's physical condition deteriorated, partially because of the merciless pace of work (and the use of amphetamine)[79] he put himself through during the writing of the Critique and a massive analytical biography of Gustave Flaubert (The Family Idiot), both of which remained unfinished. He suffered from hypertension,[80] and became almost completely blind in 1973. Sartre was a notorious chain smoker, which could also have contributed to the deterioration of his health.[81]

Sartre died on 15 April 1980 in Paris from edema of the lung. He had not wanted to be buried at Père-Lachaise Cemetery between his mother and stepfather, so it was arranged that he be buried at Montparnasse Cemetery. At his funeral on Saturday, 19 April, 50,000 Parisians descended onto boulevard du Montparnasse to accompany Sartre's cortege.[82][83] The funeral started at "the hospital at 2:00 p.m., then filed through the fourteenth arrondissement, past all Sartre's haunts, and entered the cemetery through the gate on the Boulevard Edgar Quinet". Sartre was initially buried in a temporary grave to the left of the cemetery gate.[84] Four days later the body was disinterred for cremation at Père-Lachaise Cemetery, and his ashes were reburied at the permanent site in Montparnasse Cemetery, to the right of the cemetery gate.[85]

Thought See also: Being and Nothingness

This section needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Jean-Paul Sartre" – news · newspapers · books · scholar · JSTOR (April 2019) (Learn how and when to remove this template message) Sartre's primary idea is that people, as humans, are "condemned to be free".[86][full citation needed] This theory relies upon his position that there is no creator, and is illustrated using the example of the paper cutter. Sartre says that if one considered a paper cutter, one would assume that the creator would have had a plan for it: an essence. Sartre said that human beings have no essence before their existence because there is no Creator. Thus: "existence precedes essence".[86] This forms the basis for his assertion that because one cannot explain one's own actions and behavior by referring to any specific human nature, they are necessarily fully responsible for those actions. "We are left alone, without excuse." "We can act without being determined by our past which is always separated from us."[87]

Sartre maintained that the concepts of authenticity and individuality have to be earned but not learned. We need to experience "death consciousness" so as to wake up ourselves as to what is really important; the authentic in our lives which is life experience, not knowledge.[88] Death draws the final point when we as beings cease to live for ourselves and permanently become objects that exist only for the outside world.[89] In this way death emphasizes the burden of our free, individual existence.

As a junior lecturer at the Lycée du Havre in 1938, Sartre wrote the novel La Nausée (Nausea), which serves in some ways as a manifesto of existentialism and remains one of his most famous books. Taking a page from the German phenomenological movement, he believed that our ideas are the product of experiences of real-life situations, and that novels and plays can well describe such fundamental experiences, having equal value to discursive essays for the elaboration of philosophical theories such as existentialism. With such purpose, this novel concerns a dejected researcher (Roquentin) in a town similar to Le Havre who becomes starkly conscious of the fact that inanimate objects and situations remain absolutely indifferent to his existence. As such, they show themselves to be resistant to whatever significance human consciousness might perceive in them.

He also took inspiration from phenomenologist epistemology, explained by Franz Adler in this way: "Man chooses and makes himself by acting. Any action implies the judgment that he is right under the circumstances not only for the actor, but also for everybody else in similar circumstances."[90]

This indifference of "things in themselves" (closely linked with the later notion of "being-in-itself" in his Being and Nothingness) has the effect of highlighting all the more the freedom Roquentin has to perceive and act in the world; everywhere he looks, he finds situations imbued with meanings which bear the stamp of his existence. Hence the "nausea" referred to in the title of the book; all that he encounters in his everyday life is suffused with a pervasive, even horrible, taste—specifically, his freedom. The book takes the term from Friedrich Nietzsche's Thus Spoke Zarathustra, where it is used in the context of the often nauseating quality of existence. No matter how much Roquentin longs for something else or something different, he cannot get away from this harrowing evidence of his engagement with the world.

The novel also acts as a terrifying realization of some of Immanuel Kant's fundamental ideas about freedom; Sartre uses the idea of the autonomy of the will (that morality is derived from our ability to choose in reality; the ability to choose being derived from human freedom; embodied in the famous saying "Condemned to be free") as a way to show the world's indifference to the individual. The freedom that Kant exposed is here a strong burden, for the freedom to act towards objects is ultimately useless, and the practical application of Kant's ideas proves to be bitterly rejected.

Also important is Sartre's analysis of psychological concepts, including his suggestion that consciousness exists as something other than itself, and that the conscious awareness of things is not limited to their knowledge: for Sartre intentionality applies to the emotions as well as to cognitions, to desires as well as to perceptions.[91] "When an external object is perceived, consciousness is also conscious of itself, even if consciousness is not its own object: it is a non-positional consciousness of itself."[92]

Career as public intellectual

Jean-Paul Sartre and Simone de Beauvoir at the Balzac Memorial While the broad focus of Sartre's life revolved around the notion of human freedom, he began a sustained intellectual participation in more public matters towards the end of the Second World War, around 1944–1945.[93] Before World War II, he was content with the role of an apolitical liberal intellectual: "Now teaching at a lycée in Laon ... Sartre made his headquarters the Dome café at the crossing of Montparnasse and Raspail boulevards. He attended plays, read novels, and dined [with] women. He wrote. And he was published."[94] Sartre and his lifelong companion, de Beauvoir, existed, in her words, where "the world about us was a mere backdrop against which our private lives were played out".[95][full citation needed]

Sartre portrayed his own pre-war situation in the character Mathieu, chief protagonist in The Age of Reason, which was completed during Sartre's first year as a soldier in the Second World War. By forging Mathieu as an absolute rationalist, analyzing every situation, and functioning entirely on reason, he removed any strands of authentic content from his character and as a result, Mathieu could "recognize no allegiance except to [him]self",[96][full citation needed] though he realized that without "responsibility for my own existence, it would seem utterly absurd to go on existing".[97][full citation needed] Mathieu's commitment was only to himself, never to the outside world. Mathieu was restrained from action each time because he had no reasons for acting. Sartre then, for these reasons, was not compelled to participate in the Spanish Civil War, and it took the invasion of his own country to motivate him into action and to provide a crystallization of these ideas. It was the war that gave him a purpose beyond himself, and the atrocities of the war can be seen as the turning point in his public stance.

The war opened Sartre's eyes to a political reality he had not yet understood until forced into continual engagement with it: "the world itself destroyed Sartre's illusions about isolated self-determining individuals and made clear his own personal stake in the events of the time."[98] Returning to Paris in 1941 he formed the "Socialisme et Liberté" resistance group. In 1943, after the group disbanded, Sartre joined a writers' Resistance group,[99] in which he remained an active participant until the end of the war. He continued to write ferociously, and it was due to this "crucial experience of war and captivity that Sartre began to try to build up a positive moral system and to express it through literature".[100]

The symbolic initiation of this new phase in Sartre's work is packaged in the introduction he wrote for a new journal, Les Temps modernes, in October 1945. Here he aligned the journal, and thus himself, with the Left and called for writers to express their political commitment.[101] Yet, this alignment was indefinite, directed more to the concept of the Left than a specific party of the Left.

Sartre's philosophy lent itself to his being a public intellectual. He envisaged culture as a very fluid concept; neither pre-determined, nor definitely finished; instead, in true existential fashion, "culture was always conceived as a process of continual invention and re-invention." This marks Sartre, the intellectual, as a pragmatist, willing to move and shift stance along with events. He did not dogmatically follow a cause other than the belief in human freedom, preferring to retain a pacifist's objectivity. It is this overarching theme of freedom that means his work "subverts the bases for distinctions among the disciplines".[102] Therefore, he was able to hold knowledge across a vast array of subjects: "the international world order, the political and economic organisation of contemporary society, especially France, the institutional and legal frameworks that regulate the lives of ordinary citizens, the educational system, the media networks that control and disseminate information. Sartre systematically refused to keep quiet about what he saw as inequalities and injustices in the world."[103]

Sartre always sympathized with the Left, and supported the French Communist Party (PCF) until the 1956 Soviet invasion of Hungary. Following the Liberation the PCF were infuriated by Sartre's philosophy, which appeared to lure young French men and women away from the ideology of communism and into Sartre's own existentialism.[104] From 1956 onwards Sartre rejected the claims of the PCF to represent the French working classes, objecting to its "authoritarian tendencies". In the late 1960s Sartre supported the Maoists, a movement that rejected the authority of established communist parties.[3] However, despite aligning with the Maoists, Sartre said after the May events: "If one rereads all my books, one will realize that I have not changed profoundly, and that I have always remained an anarchist."[105] He would later explicitly allow himself to be called an anarchist.[106][107]

In the aftermath of a war that had for the first time properly engaged Sartre in political matters, he set forth a body of work which "reflected on virtually every important theme of his early thought and began to explore alternative solutions to the problems posed there".[108] The greatest difficulties that he and all public intellectuals of the time faced were the increasing technological aspects of the world that were outdating the printed word as a form of expression. In Sartre's opinion, the "traditional bourgeois literary forms remain innately superior", but there is "a recognition that the new technological 'mass media' forms must be embraced" if Sartre's ethical and political goals as an authentic, committed intellectual are to be achieved: the demystification of bourgeois political practices and the raising of the consciousness, both political and cultural, of the working class.[109]

The struggle for Sartre was against the monopolising moguls who were beginning to take over the media and destroy the role of the intellectual. His attempts to reach a public were mediated by these powers, and it was often these powers he had to campaign against. He was skilled enough, however, to circumvent some of these issues by his interactive approach to the various forms of media, advertising his radio interviews in a newspaper column for example, and vice versa.[110]

The role of a public intellectual can lead to the individual placing himself in danger as he engages with disputed topics. In Sartre's case, this was witnessed in June 1961, when a plastic bomb exploded in the entrance of his apartment building. His public support of Algerian self-determination at the time had led Sartre to become a target of the campaign of terror that mounted as the colonists' position deteriorated. A similar occurrence took place the next year and he had begun to receive threatening letters from Oran, Algeria.[111]

Literature [icon] This section needs expansion. You can help by adding to it. (July 2018) Sartre wrote successfully in a number of literary modes and made major contributions to literary criticism and literary biography. His plays are richly symbolic and serve as a means of conveying his philosophy. The best-known, Huis-clos (No Exit), contains the famous line "L'enfer, c'est les autres", usually translated as "Hell is other people."[112] Aside from the impact of Nausea, Sartre's major work of fiction was The Roads to Freedom trilogy which charts the progression of how World War II affected Sartre's ideas. In this way, Roads to Freedom presents a less theoretical and more practical approach to existentialism.

John Huston got Sartre to script his film Freud: The Secret Passion.[113][full citation needed] However it was too long and Sartre withdrew his name from the film's credits.[114] Nevertheless, many key elements from Sartre's script survive in the finished film.[115]

Despite their similarities as polemicists, novelists, adapters, and playwrights, Sartre's literary work has been counterposed, often pejoratively, to that of Camus in the popular imagination. In 1948 the Roman Catholic Church placed Sartre's oeuvre on the Index Librorum Prohibitorum (List of Prohibited Books).

Criticism Some philosophers argue that Sartre's thought is contradictory. Specifically, they believe that Sartre makes metaphysical arguments despite his claim that his philosophical views ignore metaphysics. Herbert Marcuse criticized Being and Nothingness for projecting anxiety and meaninglessness onto the nature of existence itself: "Insofar as Existentialism is a philosophical doctrine, it remains an idealistic doctrine: it hypostatizes specific historical conditions of human existence into ontological and metaphysical characteristics. Existentialism thus becomes part of the very ideology which it attacks, and its radicalism is illusory."[116] In Letter on Humanism, Heidegger criticized Sartre's existentialism:

Existentialism says existence precedes essence. In this statement he is taking existentia and essentia according to their metaphysical meaning, which, from Plato's time on, has said that essentia precedes existentia. Sartre reverses this statement. But the reversal of a metaphysical statement remains a metaphysical statement. With it, he stays with metaphysics, in oblivion of the truth of Being.[117]

The philosophers Richard Wollheim and Thomas Baldwin have argued that Sartre's attempt to show that Sigmund Freud's theory of the unconscious is mistaken was based on a misinterpretation of Freud.[118][119] Richard Webster considers Sartre one of many modern thinkers who have reconstructed Judaeo-Christian orthodoxies in secular form.[120]

Intellectuals associated with the political right allege that Sartre's politics are indicative of authoritarianism. Brian C. Anderson denounced Sartre as an apologist for tyranny and terror and a supporter of Stalinism, Maoism, and Castro's regime in Cuba.[121] The historian Paul Johnson asserted that Sartre's ideas had inspired the Khmer Rouge leadership: "The events in Cambodia in the 1970s, in which between one-fifth and one-third of the nation was starved to death or murdered, were entirely the work of a group of intellectuals, who were for the most part pupils and admirers of Jean-Paul Sartre – 'Sartre's Children' as I call them."[122]

Sartre, who stated in his preface to Frantz Fanon's The Wretched of the Earth that, "To shoot down a European is to kill two birds with one stone, to destroy an oppressor and the man he oppresses at the same time: there remains a dead man and a free man", has been criticized by Anderson and Michael Walzer for supporting the killing of European civilians by the FLN during the Algerian War. Walzer suggests that Sartre, a European, was a hypocrite for not volunteering to be killed.[121][123]

The critic, poet, essayist and philosopher Clive James excoriated Sartre in his book of mini biographies Cultural Amnesia (2007). James attacks Sartre's philosophy as being "all a pose".[124]

Works Plays, screenplays, novels, and short stories Nausea / La nausée (1938) The Wall / Le mur (1939) Bariona / Bariona, ou le fils du tonnerre (1940) The Flies / Les mouches (1943) No Exit / Huis clos (1944) Typhus, wr. '44, pub. '07; adapted as The Proud and the Beautiful The Age of Reason / L'âge de raison (1945) The Reprieve / Le sursis (1945) The Respectful Prostitute / La putain respectueuse (1946) The Victors / Morts sans sépulture (1946) The Chips Are Down / Les jeux sont faits (screenplay, dir. Jean Delannoy; 1947) In the Mesh / L'engrénage (1948) Dirty Hands / Les mains sales (1948) Troubled Sleep (London ed. (Hamilton) has title: Iron in the soul) / La mort dans l'âme (1949) Intimacy (1949) The Devil and the Good Lord / Le diable et le bon dieu (1951) Kean (1953) Nekrassov (1955) The Crucible (screenplay, 1957; dir. Raymond Rouleau) The Condemned of Altona / Les séquestrés d'Altona (1959) Hurricane over Cuba / written and printed in 1961 in Brazil, along with Rubem Braga and Fernando Sabino (1961) Freud: The Secret Passion (screenplay, 1962; dir. John Huston) The Trojan Women / Les Troyennes (1965) The Freud Scenario / Le scénario Freud (1984) Philosophic essays Imagination: A Psychological Critique / L'imagination (1936) The Transcendence of the Ego / La transcendance de l'égo (1937) Sketch for a Theory of the Emotions / Esquisse d'une théorie des émotions (1939) The Imaginary / L'imaginaire (1940) Being and Nothingness / L'être et le néant (1943) Existentialism is a Humanism / L'existentialisme est un humanisme (1946) Existentialism and Human Emotions / Existentialisme et émotions humaines (1957) Search for a Method / Question de méthode (1957) Critique of Dialectical Reason / Critique de la raison dialectique (1960, 1985) Notebooks for an Ethics / Cahiers pour une morale (1983) Truth and Existence / Vérité et existence (1989) Critical essays Anti-Semite and Jew / Réflexions sur la question juive (wr. 1944, pub. 1946) Baudelaire (1946) Situations I: Literary Critiques / Critiques littéraires (1947)[125] Situations II: What Is Literature? / Qu'est-ce que la littérature ? (1947) "Black Orpheus" / "Orphée noir" (1948) Situations III (1949) Saint Genet, Actor and Martyr / S.G., comédien et martyr (1952)[126] The Henri Martin Affair / L'affaire Henri Martin (1953) Situations IV: Portraits (1964) Situations V: Colonialism and Neocolonialism (1964) Situations VI: Problems of Marxism, Part 1 (1966) Situations VII: Problems of Marxism, Part 2 (1967) The Family Idiot / L'idiot de la famille (1971–72) Situations VIII: Autour de 1968 (1972) Situations IX: Mélanges (1972) Situations X: Life/Situations: Essays Written and Spoken / Politique et Autobiographie (1976) Autobiographical Sartre By Himself / Sartre par lui-mème (1959) The Words / Les Mots (1964)[126] Witness to My Life & Quiet Moments in a War / Lettres au Castor et à quelques autres (1983) War Diaries: Notebooks from a Phony War / Les carnets de la drole de guerre (1984) See also flag France portal Biography portal Atheistic existentialism Sartre's Roads to Freedom Trilogy Situation (Sartre) References At the time, the ENS was part of the University of Paris according to the decree of 10 November 1903. Schrift, Alan D. (2006). Twentieth-century French Philosophy: Key Themes and Thinkers. Blackwell Publishing. pp. 174–5. ISBN 1-4051-3217-5. "Jean-Paul Sartre". Stanford Encyclopedia of Philosophy. Retrieved 27 October 2011. Sartre, J.-P. 2004 [1937]. The Transcendence of the Ego. Trans. Andrew Brown. Routledge, p. 7. Siewert, Charles, "Consciousness and Intentionality", The Stanford Encyclopedia of Philosophy (Fall 2011 Edition), Edward N. Zalta (ed.). Ian H. Birchall, Sartre against Stalinism, Berghahn Books, 2004, p. 176: "Sartre praised highly [Lefebvre's] work on sociological methodology, saying of it: 'It remains regrettable that Lefebvre has not found imitators among other Marxist intellectuals'." "Sartre's Debt to Rousseau" (PDF). Retrieved 2 March 2

View Details

Leary believed that the first four of these circuits ("the Larval Circuits" or "Terrestrial Circuits") are naturally accessed by most people in their lifetimes, triggered at natural transition points in life such as puberty. The second four circuits ("the Stellar Circuits" or "Extra-Terrestrial Circuits"), Leary wrote, were "evolutionary offshoots" of the first four that would be triggered at transition points which humans might acquire if they evolve. These circuits, according to Leary, would equip humans to encompass life in space, as well as the expansion of consciousness that would be necessary to make further scientific and social progress. Leary suggested that some people may "shift to the latter four gears", i.e., trigger these circuits artificially via consciousness-altering techniques such as meditation and spiritual endeavors such as yoga, or by taking psychedelic drugs specific to each circuit. The feeling of floating and uninhibited motion experienced by users of marijuana is one thing that Leary cited as evidence for the purpose of the "higher" four circuits. In the eight-circuit model of consciousness, a primary theoretical function of the fifth circuit (the first of the four, according to Leary, developed for life in outer space) is to allow humans to become accustomed to life in a zero- or low-gravity environment.[94]

Legal troubles

BNDD agents Don Strange (right) and Howard Safir (left) arrest Leary in 1972. Leary's first run-in with the law came on December 23, 1965, when he was arrested for possession of marijuana.[95][96] Leary took his two children, Jack and Susan, and his girlfriend Rosemary Woodruff to Mexico for an extended stay to write a book. On their return from Mexico to the United States, a US Customs Service official found marijuana in Susan's underwear. They had crossed into Nuevo Laredo, Mexico in the late afternoon and discovered that they would have to wait until morning for the appropriate visa for an extended stay. They decided to cross back into Texas to spend the night, and were on the US-Mexico bridge when Rosemary remembered that she had a small amount of marijuana in her possession. It was impossible to throw it out on the bridge, so Susan put it in her underwear.[97] After taking responsibility for the controlled substance, Leary was convicted of possession under the Marihuana Tax Act of 1937 on March 11, 1966, sentenced to 30 years in prison, fined $30,000, and ordered to undergo psychiatric treatment. He appealed the case on the basis that the Marihuana Tax Act was unconstitutional, as it required a degree of self-incrimination in blatant violation of the Fifth Amendment.

On December 26, 1968, Leary was arrested again in Laguna Beach, California, this time for the possession of two marijuana "roaches". Leary alleged that they were planted by the arresting officer, but was convicted of the crime. On May 19, 1969, The Supreme Court concurred with Leary in Leary v. United States, declared the Marihuana Tax Act unconstitutional, and overturned his 1965 conviction.[98]

On that same day, Leary announced his candidacy for Governor of California against the Republican incumbent, Ronald Reagan. His campaign slogan was "Come together, join the party." On June 1, 1969, Leary joined John Lennon and Yoko Ono at their Montreal Bed-In, and Lennon subsequently wrote Leary a campaign song called "Come Together".[99]

On January 21, 1970, Leary received a 10-year sentence for his 1968 offense, with a further 10 added later while in custody for a prior arrest in 1965, for a total of 20 years to be served consecutively. On his arrival in prison, he was given psychological tests used to assign inmates to appropriate work details. Having designed some of these tests himself (including the "Leary Interpersonal Behavior Inventory"), Leary answered them in such a way that he seemed to be a very conforming, conventional person with a great interest in forestry and gardening.[100] As a result, he was assigned to work as a gardener in a lower-security prison from which he escaped in September 1970, saying that his non-violent escape was a humorous prank and leaving a challenging note for the authorities to find after he was gone.[citation needed]

For a fee of $25,000, paid by The Brotherhood of Eternal Love, the Weathermen smuggled Leary out of prison in a pickup truck driven by Clayton Van Lydegraf.[101] The truck met Leary after he had escaped over the prison wall by climbing along a telephone wire. The Weathermen then helped both Leary and Rosemary out of the US (and eventually into Algeria).[102] He sought the patronage of Eldridge Cleaver for $10,000 and the remnants of the Black Panther Party's "government in exile" in Algeria, but after a short stay with them said that Cleaver had attempted to hold him and his wife hostage.[103][104] Cleaver had put Leary and his wife under "house arrest" due to exasperation with their socialite lifestyle.[104]

In 1971, the couple fled to Switzerland, where they were sheltered and effectively imprisoned by a high-living arms dealer, Michel Hauchard, who claimed he had an "obligation as a gentleman to protect philosophers"; Hauchard intended to broker a surreptitious film deal, and forced Leary to assign his future earnings (which Leary eventually won back).[62][105] In 1972, President Richard Nixon's attorney general, John Mitchell, persuaded the Swiss government to imprison Leary, which it did for a month, but refused to extradite him to the United States.[105]

Leary and Rosemary separated later that year; she traveled widely, then moved back to the United States where she lived as a fugitive until the 1990s.[105] Shortly after his separation from Rosemary in 1972, Leary became involved with Swiss-born British socialite Joanna Harcourt-Smith, a stepdaughter of financier Árpád Plesch and ex-girlfriend of Hauchard.[105] The couple "married" in a hotel under the influence of cocaine and LSD two weeks after they were first introduced, and Harcourt-Smith would use his surname until their breakup in early 1977. They traveled to Vienna, then Beirut, and finally ended up in Kabul, Afghanistan in 1972; according to Luc Sante, "Afghanistan had no extradition treaty with the United States, but this stricture did not apply to American airliners."[62] That interpretation of the law was used by American authorities to interdict the fugitive. "Before Leary could deplane, he was arrested by an agent of the federal Bureau of Narcotics and Dangerous Drugs."[62] Leary asserted a different story on appeal before the California Court of Appeal for the Second District, namely:[106]

He testified further that he had a valid passport in Kabul and that it was confiscated while he was in a line at the American Embassy in Kabul a few days prior to the day when he boarded the airplane; after his passport was confiscated, he was taken to "Central Police Headquarters"; he did not attempt to contact the American Embassy; the Kabul police held him in custody and took him to a "police hotel". The cousin of the King of Afghanistan came to see him and told him that it was a national holiday, that the King and the officials were out of Kabul, and that he (the cousin) would get a lawyer and see that Leary "had a hearing". On the morning the airplane left Kabul, officials of Afghanistan told him he was to leave Afghanistan. Leary replied he would not leave without a hearing and until he got his passport back; they said the Americans had his passport, and he was taken to the airplane.

His bail was set at $5 million.[105][107] The judge at his remand hearing stated, "If he is allowed to travel freely, he will speak publicly and spread his ideas,"[108] Facing a total of 95 years in prison, Leary hired criminal defense attorney Bruce Margolin. Leary mostly directed his own defense strategy, which proved to be unsuccessful, as the jury convicted him after deliberating for less than two hours.[105] The Brotherhood drug conspiracy charges were dropped for lack of evidence, but Leary received five years for his prison escape added to his original 10-year sentence.[105] In 1973, he was sent to Folsom Prison in California, and put in solitary confinement.[105][109] While in Folsom, he was placed in a cell right next to Charles Manson, and though they could not see each other, they could talk together. In their discussions, Manson was surprised and found it difficult to understand why Leary had given people LSD without trying to control them. At one point, Manson said to Leary, "They took you off the streets so that I could continue with your work."[110]

Leary became an informant for the FBI in order shorten his prison sentence and he entered the witness protection program upon his release in 1976.[111][112] He claimed that he feigned cooperation with the FBI investigation of Weathermen and its radical attorneys by giving them information that they already had or which he saw as being of little consequence; in response, the FBI gave him the code name "Charlie Thrush".[113] In a 1974 news conference, Allen Ginsberg, Ram Dass, and Leary's 25-year-old son Jack denounced Leary, calling Leary a "cop informant," a "liar," and a "paranoid schizophrenic."[114] Leary would later claim, and members of the Weathermen would later support his claim, that no one was ever prosecuted based on any information he gave to the FBI. In 1999, a letter was written by 22 'Friends of Timothy Leary' in an attempt to defend his reputation in light of the publication of FBI files relating to the same case. It was signed by authors such as Douglas Rushkoff, Ken Kesey, and Robert Anton Wilson. Susan Sarandon, Genesis P-Orridge and Leary's goddaughter Winona Ryder also signed the letter.[104][115]

Histories written about the Weather Underground usually mention the Leary chapter in terms of the escape for which they proudly took credit. Leary sent information to the Weather Underground through a sympathetic prisoner that he was considering making a deal with the FBI and waited for their approval. The return message was, "We understand."[115][116]

The letter writers did not provide confirmation that the Weather Underground okayed his cooperation with the FBI. While in prison, Leary was sued by the parents of Vernon Powell Cox, who had jumped from a third story window of a Berkeley apartment while under the influence of LSD. Cox had taken the drug after attending a lecture, given by Leary, favoring LSD use. Leary was unable to be present due to his incarceration, and unable to arrange for legal representation; a default judgement was entered against him in the amount of $100,000.[117]

Post prison Leary was released from prison on April 21, 1976 by Governor Jerry Brown. He stayed briefly in San Diego, then took up residence in Laurel Canyon, where he continued to write books and appear as a lecturer and "stand-up philosopher".[118] In 1978, he married filmmaker Barbara Blum, also known as Barbara Chase, sister of actress Tanya Roberts. He adopted Blum's son Zachary and raised him as his own. He also took on several godchildren, including actress Winona Ryder (the daughter of his archivist Michael Horowitz) and MIT Media Lab director Joi Ito.[119][120]

Leary began to foster an improbable friendship with former foe G. Gordon Liddy, the Watergate burglar and conservative radio talk-show host. They toured the lecture circuit in 1982 as ex-cons debating a range of social and fiscal issues, including gay rights, abortion, welfare, and the environment. Leary generally espoused left-wing views, while Liddy held to a right-wing stance. The tour generated massive publicity and considerable funds for both, and Leary was returned to the spotlight through the personal appearances, the documentary Return Engagement which chronicled the tour, and the concurrent release of the autobiography Flashbacks. In 1988, he held a fundraiser for Libertarian presidential candidate Ron Paul.[121][122]

Leary's extensive touring on the lecture circuit ensured him a very comfortable lifestyle by the mid-1980s. He also attracted a more intellectual crowd, including Robert Anton Wilson, science fiction writers William Gibson and Norman Spinrad, and rock musicians David Byrne and John Frusciante.[citation needed] In addition, he appeared in Johnny Depp's and Gibby Haynes's 1994 film Stuff, which showed Frusciante's squalid living conditions at that time.[123]

Leary continued his frequent drug use privately, rather than evangelizing and proselytizing the use of psychedelics as he had in the 1960s. Instead, he preached on the notions of space colonization and an ensuing extension of the human lifespan, while also providing a detailed explanation of the eight-circuit model of consciousness in books such as Info-Psychology: A Re-Vision of Exo-Psychology and others.[105] He invented the acronym "SMI²LE" as a succinct summary of his pre-transhumanist agenda: SM (Space Migration) + I² (intelligence increase) + LE (Life extension).[124]

Allen Ginsberg, Timothy Leary, and John C. Lilly in 1991 Leary's colonization plan changed greatly through the years. According to his initial plan to leave the planet, 5,000 of Earth's most virile and intelligent individuals would be launched on a vessel (Starseed 1) equipped with luxurious amenities. This idea was inspired by the plot line of Paul Kantner's concept album Blows Against The Empire, which in turn was derived from Robert A. Heinlein's Lazarus Long series. Leary was jailed in Folsom Prison during the winter of 1975-76, and he became enamoured by Gerard O'Neill's plans to construct giant Eden-like High Orbital Mini-Earths, as documented in the Robert Anton Wilson lecture H.O.M.E.s on LaGrange, using raw materials from the moon, orbital rock, and obsolete satellites.[125]

In the 1980s, Leary became fascinated by computers, the Internet, and virtual reality. He proclaimed that "the PC is the LSD of the 1990s" and admonished bohemians to "turn on, boot up, jack in".[126][127] He became a promoter of virtual reality systems,[128] and sometimes demonstrated a prototype of the Mattel Power Glove as part of his lectures (as in From Psychedelics to Cybernetics). He befriended a number of notable people in the field, such as Jaron Lanier[129] and Brenda Laurel, a pioneering researcher in virtual environments and human–computer interaction. With the rise of cyberdelic counter-culture, he served as consultant to Billy Idol in the production of the 1993 album Cyberpunk.[130]

In 1990, his daughter Susan (age 42) was arrested in Los Angeles for shooting her boyfriend in the head as he slept. She was ruled mentally unfit to stand trial on two occasions. She committed suicide in jail by hanging herself with a shoelace, after years of mental instability.[131][132][133] Leary and Barbara divorced in 1992, and he ensconced himself in a circle of artists and cultural figures as diverse as Johnny Depp, Susan Sarandon, Dan Aykroyd, Zach Leary,[104] author Douglas Rushkoff, and Spin magazine publisher Bob Guccione, Jr [134] Despite declining health, he maintained a regular schedule of public appearances through 1994.[135] In the same year, he was honored at a symposium of the American Psychological Association.[136]

From 1989 on, Leary had begun to re-establish his connection to unconventional religious movements with an interest in altered states of consciousness. In 1989, he appeared with friend and book collaborator Robert Anton Wilson in a dialog entitled The Inner Frontier for the Association for Consciousness Exploration, a Cleveland-based group that had been responsible for his first Cleveland appearance in 1979. After that, he appeared at the Starwood Festival, a major Neo-Pagan event run by ACE in 1992 and 1993[137] although his planned 1994 WinterStar Symposium appearance was cancelled due to his declining health. In front of hundreds of Neo-Pagans in 1992 he declared, "I've always considered myself a Pagan."[138] He also collaborated with Eric Gullichsen on Load and Run High-tech Paganism: Digital Polytheism.[139] Shortly before his death on May 31, 1996, he recorded the Right to Fly album with Simon Stokes which was released in July 1996.[140]

Death

Etoy agents with mortal remains of Timothy Leary in 2007 In January 1995, Leary was diagnosed with inoperable prostate cancer.[141] He then notified Ram Dass and other old friends, and began the process of directed dying, which he termed "designer dying."[142] Leary did not reveal the condition to the press at that time, but did so after the death of Jerry Garcia in August.[142] Leary and Ram Dass reunited before Leary's death in May 1996, as seen in the documentary film Dying to Know: Ram Dass & Timothy Leary.[143][144]

Timothy Leary reunites with Ram Dass five days before his death Leary's last book before he died was Chaos and Cyber Culture, published in 1994. In it he wrote, "The time has come to talk cheerfully and joke sassily about personal responsibility for managing the dying process."[142] His book Design for Dying, which tried to give a new perspective on death and dying, was published posthumously.[145] Leary wrote about his belief that death is "a merging with the entire life process."[145]

His website team, led by Chris Graves, updated his website on a daily basis as a sort of proto-blog.[142] The website noted his daily intake of various illicit and legal chemical substances with a predilection for nitrous oxide, LSD and other psychedelic drugs.[citation needed] He was noted for his strong views against the use of drugs which "dull the mind" such as heroin, morphine and (more than occasional) alcohol, and also for his trademark "Leary Biscuits" (a snack cracker with cheese and a small marijuana bud, briefly microwaved).[citation needed] At his request, his sterile house was redecorated by the staff with an array of surreal ornamentation.[citation needed] In his final months, thousands of visitors, well-wishers and old friends visited him in his California home.[citation needed] Until his last weeks, he gave many interviews discussing his new philosophy of embracing death.[145]

Movie poster for Timothy Leary's Dead. Leary was reportedly excited for a number of years by the possibility of freezing his body in cryonic suspension, and he publicly announced in September 1988 that he had signed up with Alcor for such treatment after having appeared at Alcor's grand opening the year before.[146] He did not believe he would be resurrected in the future, but did believe that cryonics had important possibilities even though he thought it had only "one chance in a thousand".[146] He called it his "duty as a futurist", and helped publicize the process and hoped it would work for his children and grandchildren if not for him, although he said he was "lighthearted" about it.[146] He was connected with two cryonic organizations, first Alcor and then CryoCare, one of which delivered a cryonic tank to his house in the months before his death. Leary initially announced he would freeze his entire body, but due to lack of funds decided to freeze his head only.[104][142] He then changed his mind again, and requested that his body be cremated, with his ashes scattered in space.[104]

Leary died at 75 on May 31, 1996. His death was videotaped for posterity at his request, by Denis Berry and Joey Cavella, capturing his final words.[104] Berry was the trustee of Leary's archives, and Cavella had filmed Leary during his later years.[104] According to his son Zachary, during his final moments, he clenched his fist and said, "Why?", and then unclenching his fist, he said, "Why not?". He uttered the phrase repeatedly, in different intonations, and died soon after. His last word, according to Zach, was "beautiful."[147]

The film Timothy Leary's Dead (1996) contains a simulated sequence in which he allows his bodily functions to be suspended for the purposes of cryonic preservation. His head is removed, and placed on ice. The film ends with a sequence showing the creation of the artificial head used in the film.

Seven grams of Leary's ashes were arranged by his friend at Celestis to be buried in space aboard a rocket carrying the remains of 23 others, including Gene Roddenberry (creator of Star Trek), Gerard O'Neill (space physicist), and Krafft Ehricke (rocket scientist). A Pegasus rocket containing their remains was launched on April 21, 1997, and remained in orbit for six years until it burned up in the atmosphere.[148]

Leary's ashes were also given to close friends and family. In 2015, Susan Sarandon brought some of his ashes to the Burning Man festival in Black Rock City, Nevada, and put them into an art installation there. The ashes were burned, along with the installation, on September 6, 2015.[149]

Personal life Leary was married five times, and fathered two children.

1945-1955 Marianne Busch[150] (1921-1955) daughter Susan[151] (1947-1990) son Jack[152] (1949- ) 1956-1957 Mary Cioppa[153] (1920-1996) 1964-1965 Nena von Schlebrügge (1941- ) 1967-1976 Rosemary Woodruff[154] (1935-2002) 1978-1992 Barbara Blum Chase[155][156][157] son Zach (adopted)[158] Influence Timothy Leary was an early influence on game theory applied to psychology, having introduced the concept to the International Association of Applied Psychology in 1961 at their annual conference in Copenhagen.[159][160][161][162]

He was also an early influence on transactional analysis.[163][164] His concept of the four life scripts, dating back to 1951,[165] became an influence on transactional analysis by the late 1960s, popularised by Thomas Harris in his book, I'm OK, You're OK.[166]

Many consider Leary one of the most prominent figures during the counterculture of the 1960s, and since those times has remained influential on pop culture, literature, television,[159] film and, especially, music.

Leary coined the influential term reality tunnel, by which he means a kind of representative realism. The theory states that, with a subconscious set of mental filters formed from their beliefs and experiences, every individual interprets the same world differently, hence "Truth is in the eye of the beholder".[167]

His ideas influenced the work of his friend Robert Anton Wilson. This influence went both ways, and Leary admittedly took just as much from Wilson. Wilson's book Prometheus Rising was an in-depth, highly detailed and inclusive work documenting Leary's eight-circuit model of consciousness. Although the theory originated in discussions between Leary and a Hindu holy man at Millbrook, Wilson was one of the most ardent proponents of it and introduced the theory to a mainstream audience in 1977's bestselling Cosmic Trigger. In 1989, they appeared together on stage in a dialog entitled The Inner Frontier[168] hosted by the Association for Consciousness Exploration,[169] (the same group that had hosted Leary's first Cleveland appearance in 1979).[170][171]

World religion scholar Huston Smith was "turned on" by Leary after being introduced to him by Aldous Huxley in the early 1960s. The experience was interpreted as a deeply religious one by Smith, and is described in detailed religious terms in Smith's later work Cleansing of the Doors of Perception.[172] Smith asked Leary, to paraphrase, whether he knew the power and danger of what he was conducting research with. In Mother Jones Magazine, 1997, Smith commented:

First, I have to say that during the three years I was involved with that Harvard study, LSD was not only legal but respectable. Before Tim went on his unfortunate careening course, it was a legitimate research project. Though I did find evidence that, when recounted, the experiences of the Harvard group and those of mystics were impossible to tell apart — descriptively indistinguishable — that's not the last word. There is still a question about the truth of the disclosure.[173]

In popular culture

Leary, John Lennon, Yoko Ono and others recording "Give Peace A Chance". In film The movie Fear and Loathing in Las Vegas (1998), adapted from a 1971 novel of Hunter S. Thompson, portrays heavy psychedelic drug use and mentions Leary

View Details

Allegory of the cave From Wikipedia, the free encyclopedia Jump to navigationJump to search

Plato's allegory of the cave by Jan Saenredam, according to Cornelis van Haarlem, 1604, Albertina, Vienna Part of a series on Platonism Platon.png Plato from Raphael's The School of Athens (1509–1511) Early lifeWorksEpistemologyIdealism / realismDemiurgeTheory of formsTheory of soulTranscendentalsForm of the GoodThird man argumentEuthyphro dilemmaFive regimesPhilosopher kingPlato's unwritten doctrinespolitical philosophy Allegories and metaphors AtlantisRing of GygesThe CaveThe Divided LineThe SunShip of StateMyth of ErThe Chariot Related articles CommentariesThe Academy in AthensSocratic problemMiddle PlatonismNeoplatonism and ChristianityAllegorical interpretations of PlatoSocratic fallacy Related categories Plato Socrates.png Philosophy portal vte The allegory of the cave, or Plato's Cave, was presented by the Greek philosopher Plato in his work Republic (514a–520a) to compare "the effect of education (???????) and the lack of it on our nature". It is written as a dialogue between Plato's brother Glaucon and his mentor Socrates, narrated by the latter. The allegory is presented after the analogy of the sun (508b–509c) and the analogy of the divided line (509d–511e). All three are characterized in relation to dialectic at the end of Books VII and VIII (531d–534e).

Plato has Socrates describe a group of people who have lived chained to the wall of a cave all of their lives, facing a blank wall. The people watch shadows projected on the wall from objects passing in front of a fire behind them, and give names to these shadows. The shadows are the prisoners' reality.

Socrates explains how the philosopher is like a prisoner who is freed from the cave and comes to understand that the shadows on the wall are not reality at all, for he can perceive the true form of reality rather than the manufactured reality that is the shadows seen by the prisoners. The inmates of this place do not even desire to leave their prison, for they know no better life. The prisoners manage to break their bonds one day, and discover that their reality was not what they thought it was. They discovered the sun, which Plato uses as an analogy for the fire that man cannot see behind. Like the fire that cast light on the walls of the cave, the human condition is forever bound to the impressions that are received through the senses. Even if these interpretations (or, in Kantian terminology, intuitions) are an absurd misrepresentation of reality, we cannot somehow break free from the bonds of our human condition—we cannot free ourselves from phenomenal state just as the prisoners could not free themselves from their chains. If, however, we were to miraculously escape our bondage, we would find a world that we could not understand—the sun is incomprehensible for someone who has never seen it. In other words, we would encounter another "realm", a place incomprehensible because, theoretically, it is the source of a higher reality than the one we have always known; it is the realm of pure Form, pure fact.[1]

Socrates remarks that this allegory can be paired with previous writings, namely the analogy of the sun and the analogy of the divided line.

Contents 1 Terminology 2 Summary 2.1 Imprisonment in the cave 2.2 Departure from the cave 2.3 Return to the cave 3 Symbolism 4 Themes in the allegory appearing elsewhere in Plato's work 5 Scholarly discussion 6 Influence 7 See also 8 References 9 Further reading 10 External links Terminology The allegory of the cave is also called the analogy of the cave, myth of the cave, metaphor of the cave, parable of the cave, and Plato's Cave.[2]

Summary

Allegory of the cave. Left (From top to bottom): The sun; natural things; reflections of natural things; fire; artificial objects; shadows of artificial objects; Allegory level. Right (From top to bottom): "Good" idea, Ideas, Mathematical objects, Light, Creatures and Objects, Image, analogy of the sun, and the analogy of the divided line. Imprisonment in the cave Plato begins by having Socrates ask Glaucon to imagine a cave where people have been imprisoned from childhood (important to note that they were (based on text) imprisoned from childhood but not from birth). These prisoners are chained so that their legs and necks are fixed, forcing them to gaze at the wall in front of them and not look around at the cave, each other, or themselves (514a–b).[3] Behind the prisoners is a fire, and between the fire and the prisoners is a raised walkway with a low wall, behind which people walk carrying objects or puppets "of men and other living things" (514b).[3] The people walk behind the wall so their bodies do not cast shadows for the prisoners to see, but the objects they carry do ("just as puppet showmen have screens in front of them at which they work their puppets" (514a)[3]). The prisoners cannot see any of what is happening behind them, they are only able to see the shadows cast upon the cave wall in front of them. The sounds of the people talking echo off the walls, and the prisoners believe these sounds come from the shadows (514c).[3]

Socrates suggests that the shadows are reality for the prisoners because they have never seen anything else; they do not realize that what they see are shadows of objects in front of a fire, much less that these objects are inspired by real things outside the cave which they do not see (514b–515a).[3]

The fire, or human made light, and the puppets, used to make shadows, are done by the artists. This can be compared to how illusions are made with light and sound today, with electronics, videos, movies, and 3D visuals. Plato, however, indicates that the fire is also the political doctrine that is taught in a nation state. The artists use light and shadows to teach the dominant doctrines of a time and place.

Also, few humans will ever escape the cave. This is not some easy task, and only a true philosopher, with decades of preparation, would be able to leave the cave, up the steep incline. Most humans will live at the bottom of the cave, and a small few will be the major artists that project the shadows with the use of human-made light.

Departure from the cave Plato then supposes that one prisoner is freed. This prisoner would look around and see the fire. The light would hurt his eyes and make it difficult for him to see the objects casting the shadows. If he were told that what he is seeing is real instead of the other version of reality he sees on the wall, he would not believe it. In his pain, Plato continues, the freed prisoner would turn away and run back to what he is accustomed to (that is, the shadows of the carried objects). He writes "... it would hurt his eyes, and he would escape by turning away to the things which he was able to look at, and these he would believe to be clearer than what was being shown to him."[3]

Plato continues: "Suppose... that someone should drag him... by force, up the rough ascent, the steep way up, and never stop until he could drag him out into the light of the sun."[3] The prisoner would be angry and in pain, and this would only worsen when the radiant light of the sun overwhelms his eyes and blinds him.[3]

"Slowly, his eyes adjust to the light of the sun. First he can only see shadows. Gradually he can see the reflections of people and things in water and then later see the people and things themselves. Eventually, he is able to look at the stars and moon at night until finally he can look upon the sun itself (516a)."[3] Only after he can look straight at the sun "is he able to reason about it" and what it is (516b).[3] (See also Plato's analogy of the sun, which occurs near the end of The Republic, Book VI.[4][5])

Return to the cave Plato continues, saying that the freed prisoner would think that the world outside the cave was superior to the world he experienced in the cave and attempt to share this with the prisoners remaining in the cave attempting to bring them onto the journey he had just endured; "he would bless himself for the change, and pity [the other prisoners]" and would want to bring his fellow cave dwellers out of the cave and into the sunlight (516c).[3]

The returning prisoner, whose eyes have become accustomed to the sunlight, would be blind when he re-enters the cave, just as he was when he was first exposed to the sun (516e).[3] The prisoners, according to Plato, would infer from the returning man's blindness that the journey out of the cave had harmed him and that they should not undertake a similar journey. Plato concludes that the prisoners, if they were able, would therefore reach out and kill anyone who attempted to drag them out of the cave (517a).[3]

Symbolism

This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Allegory of the cave" – news · newspapers · books · scholar · JSTOR (January 2020) (Learn how and when to remove this template message) The allegory contains many forms of symbolism used to instruct the reader in the nature of perception. The cave represents superficial physical reality. It also represents ignorance, as those in the cave live accepting what they see at face value. Ignorance is further represented by the darkness that engulfs them because they cannot know the true objects that form the shadows, leading them to believe the shadows are the true forms of the objects. The chains that prevent the prisoners from leaving the cave represent that they are trapped in ignorance, as the chains are stopping them from learning the truth. The shadows cast on the walls of the cave represent the superficial truth, which is the illusion that the prisoners see in the cave. The freed prisoner represents those who understand that the physical world is only a shadow of the truth, and the sun that is glaring the eyes of the prisoners represents the higher truth of ideas. The light further represents wisdom, as even the paltry light that makes it into the cave allows the prisoners to know shapes.

Themes in the allegory appearing elsewhere in Plato's work The allegory is probably related to Plato's theory of Forms, according to which the "Forms" (or "Ideas"), and not the material world known to us through sensation, possess the highest and most fundamental kind of reality. Only knowledge of the Forms constitutes real knowledge or what Socrates considers "the good".[6] Socrates informs Glaucon that the most excellent people must follow the highest of all studies, which is to behold the Good. Those who have ascended to this highest level, however, must not remain there but must return to the cave and dwell with the prisoners, sharing in their labors and honors.

Plato's Phaedo contains similar imagery to that of the allegory of the cave; a philosopher recognizes that before philosophy, his soul was "a veritable prisoner fast bound within his body... and that instead of investigating reality of itself and in itself is compelled to peer through the bars of a prison."[7]

Scholarly discussion Scholars debate the possible interpretations of the allegory of the cave, either looking at it from an epistemological standpoint—one based on the study of how Plato believes we come to know things—or through a political (politeia) lens.[6] Much of the scholarship on the allegory falls between these two perspectives, with some completely independent of either. The epistemological view and the political view, fathered by Richard Lewis Nettleship and A. S. Ferguson, respectively, tend to be discussed most frequently.[6] Nettleship interprets the allegory of the cave as representative of our innate intellectual incapacity, in order to contrast our lesser understanding with that of the philosopher, as well as an allegory about people who are unable or unwilling to seek truth and wisdom.[8] Ferguson, on the other hand, bases his interpretation of the allegory on the claim that the cave is an allegory of human nature and that it symbolizes the opposition between the philosopher and the corruption of the prevailing political condition.[7][8]

Cleavages have emerged within these respective camps of thought, however. Much of the modern scholarly debate surrounding the allegory has emerged from Martin Heidegger's exploration of the allegory, and philosophy as a whole, through the lens of human freedom in his book The Essence of Human Freedom: An Introduction to Philosophy and The Essence of Truth: On Plato's Cave Allegory and Theaetetus.[9] In response, Hannah Arendt, an advocate of the political interpretation of the allegory, suggests that through the allegory, Plato "wanted to apply his own theory of ideas to politics".[10] Conversely, Heidegger argues that the essence of truth is a way of being and not an object.[11] Arendt criticised Heidegger's interpretation of the allegory, writing that "Heidegger…is off base in using the cave simile to interpret and 'criticize' Plato's theory of ideas".[10]

Various scholars also debate the possibility of a connection between the work in the allegory and the cave and the work done by Plato considering the analogy of the divided line and the analogy of the sun. The divided line is a theory presented to us in Plato's work the Republic. This is displayed through a dialogue given between Socrates and Glaucon. In which they explore the possibility of a visible and intelligible world. with the visible world consisting of items such as shadows and reflections (displayed as AB) then elevating to the physical item itself (displayed as BC) while the intelligible world consists of mathematical reasoning (displayed by CD) and philosophical understanding (displayed by DE).[12] Many seeing this as an explanation to the way in which the prisoner in the allegory of the cave goes through the journey. First in the visible word with shadows such as those on the wall. Socrates suggests that the shadows are reality for the prisoners because they have never seen anything else; they do not realize that what they see are shadows of objects in front of a fire, much less that these objects are inspired by real things outside the cave which they do not see[12] then the realization of the physical with the understanding of concepts such as the tree being separate from its shadow. It enters the intelligible world as the prisoner looks at the sun. Leading to the Analogy of the Sun.[13]

The divided line – (AC) is generally taken as representing the visible world and (CE) as representing the intelligible world[14] The Analogy of the Sun refers to the moment in book six in which Socrates after being urged by Glaucon to define goodness purposes instead, an analogy through a "child of goodness". Socrates reveals this "child of goodness" to be the sun, proposing that just as the sun illuminates, bestowing the ability to see and be seen by the eye,[15]:169 with its light so the idea of goodness illumines the intelligible with truth. Leading some scholars to believe this forms a connection of the sun and the intelligible world within the realm of the allegory of the cave.

Influence The themes and imagery of Plato's cave have appeared throughout Western thought and culture. Some examples include:

Thomas Browne in his 1658 discourse Urn Burial stated: "A Dialogue between two Infants in the womb concerning the state of this world, might handsomely illustrate our ignorance of the next, whereof methinks we yet discourse in Platoes denne, and are but Embryon Philosophers". Evolutionary biologist Jeremy Griffith's book A Species In Denial includes the chapter "Deciphering Plato's Cave Allegory".[16] The films The Conformist, The Matrix, Dark City, The Truman Show, Us and City of Ember model Plato's allegory of the cave.[17][18] The 2013 movie After the Dark has a segment where Mr. Zimit likens James' life to the Allegory of the Cave.[19] This segment in the movie is at 1:05:36 – 1:07:00, and there's also a soundtrack named "Plato's Cave" on the OST album. The Cave by José Saramago culminates in the discovery of Plato's Cave underneath the Center, "an immense complex fusing the functions of an office tower, a shopping mall and a condominium."[20] Emma Donoghue acknowledges the influence of Plato's allegory of the cave on her novel Room.[21] Ray Bradbury's novel Fahrenheit 451 explores the themes of reality and perception also explored in Plato's allegory of the cave and Bradbury references Plato's work in the novel.[22][23] José Carlos Somoza's novel The Athenian Murders is presented as a murder mystery but features many references to Plato's philosophy including the allegory of the cave.[24] Novelist James Reich argues Nicholas Ray's film Rebel Without a Cause, starring James Dean, Natalie Wood, and Sal Mineo as John "Plato" Crawford is influenced by and enacts aspects of the allegory of the cave.[25] In an episode of the television show Legion, entitled "Chapter 16", the narrator uses Plato's Cave to explain "the most alarming delusion of all", narcissism. H. G. Wells' short novel The Country of the Blind has a similar "Return to the Cave" situation when a man accidentally discovers a village of blind people and wherein he tries to explain how he can "see", only to be ridiculed and laughed at.[26][circular reference] See also Allegorical interpretations of Plato Archetype Analogy of the sun Analogy of the divided line Brain in a vat Flatland The Form of the Good Intelligibility (philosophy) Nous – Noumenon Phaneron Plato's Republic in popular culture References Ferguson, A. S. "Plato's Simile of Light. (Part II.) The Allegory of the Cave (Continued)". The Classical Quarterly 16, no. 1 (1922): 15–28. JSTOR 636164. The various English names of this allegory were often traditionally capitalized as if they were the names of a chapter in Plato's text, which is not correct, or according to an older style that capitalized all (famous) allegories and theories and even concepts. Wikipedia's manual of style does not follow this older practice, and neither do many modern publications in reliable sources nor, for example, the Encyclopædia Britannica and the Columbia Encyclopedia. Plato. Rouse, W.H.D. (ed.). The Republic Book VII. Penguin Group Inc. pp. 365–401. Jowett, B. (ed.) (1941). Plato's The Republic. New York: The Modern Library. OCLC 964319. Malcolm, John (1962-01-01). "The Line and the Cave". Phronesis. 7 (1): 38–45. doi:10.1163/156852862x00025. ISSN 0031-8868. Watt, Stephen (1997), "Introduction: The Theory of Forms (Books 5–7)", Plato: Republic, London: Wordsworth Editions, pp. xiv–xvi, ISBN 978-1-85326-483-2 Elliott, R. K. (1967). "Socrates and Plato's Cave". Kant-Studien. 58 (2): 138. doi:10.1515/kant.1967.58.1-4.137. Hall, Dale. "INTERPRETING PLATO'S CAVE AS AN ALLEGORY OF THE HUMAN CONDITION." Apeiron: A Journal for Ancient Philosophy and Science 14, no. 2 (1980): 74-86. http://www.jstor.org/stable/40913453. McNiell, William. "Notre Dame Philosophical Reviews." The Essence of Human Freedom: An Introduction to Philosophy and The Essence of Truth: On Plato's Cave Allegory and Theaetetus // Reviews // Notre Dame Philosophical Reviews // University of Notre Dame. Accessed December 09, 2016. http://ndpr.nd.edu/news/23227/. Abensour, Miguel. Against the Sovereignty of Philosophy over Politics: Arendt's Reading of Plato's Cave Allegory Social Research; Winter 2007; 74, 4; ProQuest Social Sciences Premium Collection pg. 955 Powell, Sally. "Discovering the Unhidden: Heidegger's Interpretation of Plato's Allegory of the Cave and Its Implications for Psychotherapy." Existential Analysis 22, no. 1 (January 2011). Accessed December 8, 2016. Plato, The Republic, Book 6, translated by Benjamin Jowett, online Archived 18 April 2009 at the Wayback Machine Raven, J. E. “Sun, Divided Line, and Cave.” The Classical Quarterly, vol. 3, no. 1/2, 1953, pp. 22–32. JSTOR, https://www.jstor.org/stable/637158. "divided line," The Cambridge Dictionary of Philosophy, 2nd edition, Cambridge University Press, 1999, ISBN 0-521-63722-8, p. 239. Pojman, Louis & Vaughn, L. (2011). Classics of Philosophy. New York: Oxford University Press, Inc. Griffith, Jeremy (2003). A Species in Denial. Sydney: WTM Publishing & Communications. p. 83. ISBN 978-1-74129-000-4. The Matrix and Philosophy: Welcome to the Desert of the Real by William Irwin. Open Court Publishing, 2002. ISBN 0-8126-9501-1. "Written for those fans of the film who are already philosophers." "Prisoners of Plato in The Conformist". YouTube. Retrieved 2018-05-31. After the Dark - Allegory to the Cave / Plato's Cave CLIP, retrieved 2019-10-30 Keates, Jonathan. "Shadows on the Wall". The New York Times. Retrieved 24 November 2002. "Q & A with Emma Donoghue – Spoiler-friendly Discussion of Room (showing 1–50 of 55)". www.goodreads.com. Retrieved 2016-01-30. "Parallels between Ray Bradbury's Fahrenheit 69 and Plato's 'Allegory of the Cave'".[permanent dead link] Bradbury, Ray (1953). Fahrenheit 451. The Random House Publishing Group. p. 151. ISBN 978-0-758-77616-7. Somoza, Jose Carlos (2003). The Athenian Murders. ABACUS. ISBN 978-0349116181. "Plato's Cave: Rebel Without a Cause and Platonic Allegory – OUTSIDER ACADEMY". Retrieved 2017-06-25.[permanent dead link] The Country of the Blind Further reading The following is a list of supplementary scholarly literature on the Allegory of the cave that includes articles from epistemological, political, alternative, and independent viewpoints on the allegory:

Alan Kim: Shades of Truth: Phenomenological Perspectives on the Allegory of the Cave Gabriel Zamosc: The Political Significance of Plato's Allegory of the Cave Dimitra Mitta: Reading Platonic Myths from a Ritualistic Point of View: Gyges' Ring and the Cave Allegory William McNiell: The Essence of Human Freedom: An Introduction to Philosophy and the Essence of Truth: On Plato's Cave Allegory and Thaetetus Maureen Eckert: Cinematic Spelunking Inside Plato's Cave Boaz Tsabar: "Poverty and Resourcefulness": On the Formative Significance of Eros in Educational Practice J. Malcolm: The Cave Revisited N. R. Murphy: The 'Simile of Light' in Plato's Republic External links Wikiquote has quotations related to: Allegory of the cave Wikisource has original text related to this article: The Republic/Book VII Wikimedia Commons has media related to Allegory of the cave. Allegory of the cave at PhilPapers Ted-ed: Plato's Allegory of the Cave Animated interpretation of Plato's Allegory of the Cave Plato: The Republic at Project Gutenberg Plato: The Allegory of the Cave, from The Republic at University of Washington – Faculty Plato: Book VII of The Republic, Allegory of the Cave at Shippensburg University 2019 translation of the Allegory of the Cave vte Plato Life Early lifePlatonismPlatonic epistemologyPlatonic idealismPlatonic realismPlatonic loveNeoplatonism and GnosticismPlatonism in the RenaissanceCardinal virtuesDemiurgeTheory of FormsTranscendentalsForm of the GoodThird man argumentEuthyphro dilemmaFive regimesPhilosopher kingUnwritten doctrinesCultural influence of Plato's Republic Plato Silanion Musei Capitolini MC1377.jpg Works Uncontested ApologyCharmidesCratylusCritiasCritoEuthydemusEuthyphroGorgiasHippias MinorIonLaches Papyrus Oxyrhynchus 228Laws Papyrus Oxyrhynchus 23LysisMenexenusMenoParmenidesPhaedo Papyrus Oxyrhynchus 229PhaedrusPhilebusProtagorasRepublicSophistStatesmanSymposiumTheaetetusTimaeus Of doubtful authenticity AxiochusClitophonDefinitionsDemodocusEpigramsEpinomisEpistles Letter IIIIVVVIVIIIXXXIXIIEryxiasFirst AlcibiadesHalcyonHipparchusHippias MajorMinosOn JusticeOn VirtueRival LoversSecond AlcibiadesSisyphusTheages Allegories and metaphors AtlantisRing of GygesThe CaveThe Divided LineThe SunShip of StateMyth of ErThe ChariotAllegorical interpretations of Plato Family Ariston of Athens (father)Pyrilampes (stepfather)Perictione (mother)Adeimantus of Collytus (brother)Glaucon (brother)Antiphon (brother)Potone (sister)Speusippus (nephew) Related CommentariesThe Academy in AthensSocratic problemMiddle PlatonismNeoplatonism and ChristianityPoitier Meets PlatoList of speakers in Plato's dialoguesPlato's Dream Authority control Edit this at Wikidata BNF: cb12127441d (data)LCCN: sh85103329SUDOC: 029708028 Categories: AllegoryAnalogyConcepts in epistemologyMetaphysicsPlatonismPhilosophy of educationFictional caves Navigation menu Not logged inTalkContributionsCreate accountLog inArticleTalkReadEditView historySearch Search Wikipedia Main page Contents Featured content Current events Random article Donate to Wikipedia Wikipedia store Interaction Help About Wikipedia Community portal Recent changes Contact page Tools What links here Related changes Upload file Special pages Permanent link Page information Wikidata item Cite this page In other projects Wikimedia Commons Wikiquote Print/export Download as PDF Printable version

Languages ??????? Deutsch Español ?????? Bahasa Indonesia Português ??????? ?????????? ?? 42 more Edit links This page was last edited on 11 January 2020, at 22:46 (UTC).

View Details

Kubrick's Script Treatment 185 Shares 185 The Shining Treatment Deleted Scene No Film School Just when it appears there couldn't be more material about The Shining on the internet, here comes the original treatment and script for a scene Kubrick deleted after the film's release. The Shining is one of the most talked about movies of all time, and certainly, 1980's only release to be the subject of so much tortured exegetical speculation (with second and third place going, respectively, to The Empire Strikes Back and The Blues Brothers). But even 36 years after its release, the film's every scrap of ephemera still manages to obsess a certain segment of the populace (e.g. yours truly).

If you fall into that category, check out this video that depicts a deleted scene from the film, one that was shot and actually made it into the release prints, only to be recalled after the film made it into theaters. And below, read the original treatment for the film and see what didn't make the cut.

https://www.youtube.com/watch?v=GyhGd3qyOKc&feature=youtu.be&ab_channel=BlackdogTV-Cinemania

After The Shining premiered in Los Angeles and New York, Kubrick decided to delete this scene, which takes place in between the shot of Jack, frozen in the hedge maze, and the infamous final track toward the July 4 ball photo.

In his 2006 essay on the film, the late, great Roger Ebert wrote, "Kubrick is telling a story with ghosts (the two girls, the former caretaker, and a bartender), but it isn't a 'ghost story,' because the ghosts may not be present in any sense at all except as visions experienced by Jack or Danny." Later, Ebert remarked of the deleted scene, "Kubrick was wise to remove that epilogue. It pulled one rug too many out from under the story. At some level, it is necessary for us to believe the three members of the Torrance family are actually residents in the hotel during that winter, whatever happens or whatever they think happens."

You can read the full script of the deleted ending here.

"Kubrick was wise to remove that epilogue. It pulled one rug too many out from under the story." Roger Ebert

Now, Birth. Movies. Death is reporting on the original treatment that would end up as Diane Johnson and Stanley Kubrick's screenplay. It's striking for several reasons. First off, the opening titles of the film are justly famous for the haunting, remote, and icy beauty of the helicopter shots that track Jack's Volkswagen Beetle up the road to the Overlook. In the film, the viewer is afforded an omniscient (or perhaps more malevolent presence) view for the entirety of the credit sequence:

https://www.youtube.com/watch?v=TgCejsyS0t8&ab_channel=KnightKobra49

In the treatment, however, this view is interrupted by a cut into the car, where we meet Jack, crudely "studying" Spanish by talking back to his taped language lesson.

The Shining Treatment Deleted Scene No Film School BMD also notes some other differences between the film and the treatment: "...a flashback scene where an enraged Jack breaks the arm of one of his former students [is] lifted directly from King's novel, while others (like the moment where the hotel possesses Halloran, turning him evil) are brand-new to any version of The Shining." An evil Halloran is something I'm loath to imagine. There's also a potentially horrifying moment where Danny finds a bloody pair of children's shoes buried in the Overlook's sandbox, a sandbox which fails to make any appearance in the film.

This material makes for a fascinating read which, along with the deleted scene, should provide an edifying afternoon for any aficionado of the film, as well as provide an object lesson for any filmmaker: in many cases, less really is more.

source: Birth. Movies. Death. YOU MIGHT ALSO LIKE Seriously Exhaustive Analysis of 'The Shining' Shows Kubrick's Inversion of King's Novel Why That Bear Performed Fellatio on That Guy in 'The Shining' Watch: How Kubrick Adapted King's ‘The Shining’ into an Entirely Different Masterpiece Your Comment Share your thought and insights.

4 Comments Good article, but this material is not new...

August 30, 2016 at 2:52PM

0 Reply ShareavatarJosué Ramos90 Watch? That's incredibly misleading for someone like me who has dreamed of seeing this scene for years.

August 31, 2016 at 7:59AM, Edited August 31, 7:59AM

0 Reply ShareMark Frost351 "Hey Rocky, watch me pull an article out of my butt!" - from The Adventures of Rocky and Bullshitter https://www.youtube.com/watch?v=vQ2sMALs4YU

September 3, 2016 at 2:08PM, Edited September 3, 2:09PM

0 Reply ShareavatarDavid A. Barak915 It actaully screened on other screens outside of LA and New York. I know because it saw it in Michigan.

September 11, 2017 at 4:16PM, Edited September 11, 4:16PM

12 Reply ShareSassyLou76 circle The DSLR Cinematography Guide Get your FREE copy of the eBook called "astonishingly detailed and useful" by Filmmaker Magazine! It's 100+ pages on what you need to know to make beautiful, inexpensive movies using a DSLR. Subscribe to receive the free PDF!

No Film School About Subscribe Contact Advertise Community Guidelines Terms Privacy Sections Boards Topics Popular Podcasts Follow NFS circle Facebook circle Twitter circle YouTube circle RSS © 2020 NONETWORK, LLC. All Rights Reserved.No Film School

View Details

give peace and love in this world 1 second ago i dont think thats in PERU at all

faridjabba faridjabba 1 second ago where this at'¿ is he really playing ?

ISMAIL ILYAS ISMAIL ILYAS 2 years ago no one can understand the feeling for what its like to live life like a stranger in their own motherland

20K

HINDU VEDIC HINDU VEDIC 3 weeks ago Sad..... forgotten Culture and destroyed Hearts.

326

John Lam John Lam 12 hours ago (edited) When your land is taken, there’s everlasting hatred and despair. Song’s like this all ways come’s from the heart....

30

Jennifer B Jennifer B 3 weeks ago Doesn’t matter what the color of your skin is on the outside we all bleed the same! We are all human all family all united we should all love and respect each other and our world!

167

GJL GJL 2 weeks ago only HUMANS WITH SOUL, WILL UNDERSTAND THESE FEELING

176

Sam Alex Sam Alex 9 months ago The most painful thing to be a stranger in your land!!!

11K

Susan Wei Susan Wei 4 weeks ago I cried . Like it. Like Native American and their culture.

135

JOSEPH Outcast JOSEPH Outcast 3 weeks ago (edited) El dolor de ser un extrano en tu propia Tierra...

13

Drewski Brewski Drewski Brewski 2 weeks ago More talent than any junk rapper in 2019...... 140 lbs tatted up with a sold soul to Lucifer and they think their tough.... hahaha please this is a true warrior call.

View Details

Paul Time dilation From Wikipedia, the free encyclopedia Jump to navigationJump to search

Time dilation explains why two working clocks will report different times after different accelerations. For example, at the ISS time goes slower, lagging 0.007 seconds behind for every six months. For GPS satellites to work, they must adjust for similar bending of spacetime to coordinate with systems on Earth.[1] Time dilation is a difference in the elapsed time measured by two clocks, either due to them having a velocity relative to each other, or by there being a gravitational potential difference between their locations. After compensating for varying signal delays due to the changing distance between an observer and a moving clock (i.e. Doppler effect), the observer will measure the moving clock as ticking slower than a clock that is at rest in the observer's own reference frame. A clock that is close to a massive body (and which therefore is at lower gravitational potential) will record less elapsed time than a clock situated further from the said massive body (and which is at a higher gravitational potential).

These predictions of the theory of relativity have been repeatedly confirmed by experiment, and they are of practical concern, for instance in the operation of satellite navigation systems such as GPS and Galileo.[1][2] Time dilation has also been the subject of science fiction works, as it technically provides the means for forward time travel.[3]

Contents 1 History 2 Velocity time dilation 2.1 Simple inference of velocity time dilation 2.2 Reciprocity 2.3 Experimental testing 2.3.1 Doppler effect 2.3.2 Moving particles 2.4 Proper time and Minkowski diagram 2.5 Derivation and formulation 2.6 Hyperbolic motion 2.7 Clock hypothesis 3 Gravitational time dilation 3.1 Experimental testing 4 Combined effect of velocity and gravitational time dilation 4.1 Experimental testing 5 See also 6 Footnotes 7 References 8 Further reading 9 External links History Main article: History of special relativity Time dilation by the Lorentz factor was predicted by several authors at the turn of the 20th century.[4][5] Joseph Larmor (1897), at least for electrons orbiting a nucleus, wrote "... individual electrons describe corresponding parts of their orbits in times shorter for the [rest] system in the ratio :{displaystyle scriptstyle {sqrt {1-{frac {v^{2}}{c^{2}}}}}}scriptstyle {sqrt {1-{frac {v^{2}}{c^{2}}}}}".[6] Emil Cohn (1904) specifically related this formula to the rate of clocks.[7] In the context of special relativity it was shown by Albert Einstein (1905) that this effect concerns the nature of time itself, and he was also the first to point out its reciprocity or symmetry.[8] Subsequently, Hermann Minkowski (1907) introduced the concept of proper time which further clarified the meaning of time dilation.[9]

Velocity time dilation

From the local frame of reference of the blue clock, the red clock, being in motion, is perceived as ticking slower[10] (Exaggerated) Special relativity indicates that, for an observer in an inertial frame of reference, a clock that is moving relative to him will be measured to tick slower than a clock that is at rest in his frame of reference. This case is sometimes called special relativistic time dilation. The faster the relative velocity, the greater the time dilation between one another, with the rate of time reaching zero as one approaches the speed of light (299,792,458 m/s). This causes massless particles that travel at the speed of light to be unaffected by the passage of time.

Theoretically, time dilation would make it possible for passengers in a fast-moving vehicle to advance further into the future in a short period of their own time. For sufficiently high speeds, the effect is dramatic. For example, one year of travel might correspond to ten years on Earth. Indeed, a constant 1 g acceleration would permit humans to travel through the entire known Universe in one human lifetime.[11]

With current technology severely limiting the velocity of space travel, however, the differences experienced in practice are minuscule: after 6 months on the International Space Station (ISS) (which orbits Earth at a speed of about 7,700 m/s[2]) an astronaut would have aged about 0.007 seconds less than those on Earth. The cosmonauts Sergei Krikalev and Sergei Avdeyev both experienced time dilation of about 20 milliseconds compared to time that passed on Earth.[12][13]

Simple inference of velocity time dilation

Left: Observer at rest measures time 2L/c between co-local events of light signal generation at A and arrival at A. Right: Events according to an observer moving to the left of the setup: bottom mirror A when signal is generated at time t'=0, top mirror B when signal gets reflected at time t'=D/c, bottom mirror A when signal returns at time t'=2D/c Time dilation can be inferred from the observed constancy of the speed of light in all reference frames dictated by the second postulate of special relativity.[14][15][16][17]

This constancy of the speed of light means that, counter to intuition, speeds of material objects and light are not additive. It is not possible to make the speed of light appear greater by moving towards or away from the light source.

Consider then, a simple clock consisting of two mirrors A and B, between which a light pulse is bouncing. The separation of the mirrors is L and the clock ticks once each time the light pulse hits either of the mirrors.

In the frame in which the clock is at rest (diagram on the left), the light pulse traces out a path of length 2L and the period of the clock is 2L divided by the speed of light:

{displaystyle Delta t={frac {2L}{c}}.}Delta t={frac {2L}{c}}. From the frame of reference of a moving observer traveling at the speed v relative to the resting frame of the clock (diagram at right), the light pulse is seen as tracing out a longer, angled path. Keeping the speed of light constant for all inertial observers, requires a lengthening of the period of this clock from the moving observer's perspective. That is to say, in a frame moving relative to the local clock, this clock will appear to be running more slowly. Straightforward application of the Pythagorean theorem leads to the well-known prediction of special relativity:

The total time for the light pulse to trace its path is given by

{displaystyle Delta t'={frac {2D}{c}}.}Delta t'={frac {2D}{c}}. The length of the half path can be calculated as a function of known quantities as

{displaystyle D={sqrt {left({frac {1}{2}}vDelta t'right)^{2}+L^{2}}}.}{displaystyle D={sqrt {left({frac {1}{2}}vDelta t'right)^{2}+L^{2}}}.} Elimination of the variables D and L from these three equations results in

{displaystyle Delta t'={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},}{displaystyle Delta t'={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},} which expresses the fact that the moving observer's period of the clock {displaystyle Delta t'}Delta t' is longer than the period {displaystyle Delta t}Delta t in the frame of the clock itself.

Reciprocity

Time UV of a clock in S is shorter compared to Ux? in S?, and time UW of a clock in S? is shorter compared to Ux in S

Transversal time dilation. The blue dots represent a pulse of light. Each pair of dots with light "bouncing" between them is a clock. For each group of clocks, the other group appears to be ticking more slowly, because the moving clock's light pulse has to travel a larger distance than the stationary clock's light pulse. That is so, even though the clocks are identical and their relative motion is perfectly reciprocal. Given a certain frame of reference, and the "stationary" observer described earlier, if a second observer accompanied the "moving" clock, each of the observers would perceive the other's clock as ticking at a slower rate than their own local clock, due to them both perceiving the other to be the one that's in motion relative to their own stationary frame of reference.

Common sense would dictate that, if the passage of time has slowed for a moving object, said object would observe the external world's time to be correspondingly sped up. Counterintuitively, special relativity predicts the opposite. When two observers are in motion relative to each other, each will measure the other's clock slowing down, in concordance with them being moving relative to the observer's frame of reference.

While this seems self-contradictory, a similar oddity occurs in everyday life. If two persons A and B observe each other from a distance, B will appear small to A, but at the same time A will appear small to B. Being familiar with the effects of perspective, there is no contradiction or paradox in this situation.[18]

The reciprocity of the phenomenon also leads to the so-called twin paradox where the aging of twins, one staying on Earth and the other embarking on a space travel, is compared, and where the reciprocity suggests that both persons should have the same age when they reunite. On the contrary, at the end of the round-trip, the traveling twin will be younger than his brother on Earth. The dilemma posed by the paradox, however, can be explained by the fact that the traveling twin must markedly accelerate in at least three phases of the trip (beginning, direction change, and end), while the other will only experience negligible acceleration, due to rotation and revolution of Earth. During the acceleration phases of the space travel, time dilation is not symmetric.

Experimental testing See also: Tests of special relativity Doppler effect Main article: Ives–Stilwell experiment The stated purpose by Ives and Stilwell (1938, 1941) of these experiments was to verify the time dilation effect, predicted by Larmor–Lorentz ether theory, due to motion through the ether using Einstein's suggestion that Doppler effect in canal rays would provide a suitable experiment. These experiments measured the Doppler shift of the radiation emitted from cathode rays, when viewed from directly in front and from directly behind. The high and low frequencies detected were not the classically predicted values {displaystyle {frac {f_{0}}{1-v/c}}qquad {text{and}}qquad {frac {f_{0}}{1+v/c}}.,}{frac {f_{0}}{1-v/c}}qquad {text{and}}qquad {frac {f_{0}}{1+v/c}}., The high and low frequencies of the radiation from the moving sources were measured as[19] {displaystyle {sqrt {frac {1+v/c}{1-v/c}}}f_{0}=gamma left(1+v/cright)f_{0}qquad {text{and}}qquad {sqrt {frac {1-v/c}{1+v/c}}}f_{0}=gamma left(1-v/cright)f_{0},,}{sqrt {frac {1+v/c}{1-v/c}}}f_{0}=gamma left(1+v/cright)f_{0}qquad {text{and}}qquad {sqrt {frac {1-v/c}{1+v/c}}}f_{0}=gamma left(1-v/cright)f_{0},, as deduced by Einstein (1905) from the Lorentz transformation, when the source is running slow by the Lorentz factor. Hasselkamp, Mondry, and Scharmann[20] (1979) measured the Doppler shift from a source moving at right angles to the line of sight. The most general relationship between frequencies of the radiation from the moving sources is given by: {displaystyle f_{mathrm {detected} }=f_{mathrm {rest} }{left(1-{frac {v}{c}}cos phi right)/{sqrt {1-{v^{2}}/{c^{2}}}}}}f_{mathrm {detected} }=f_{mathrm {rest} }{left(1-{frac {v}{c}}cos phi right)/{sqrt {1-{v^{2}}/{c^{2}}}}} as deduced by Einstein (1905).[21] For ? = 90° (cos ? = 0) this reduces to fdetected = frest?. This lower frequency from the moving source can be attributed to the time dilation effect and is often called the transverse Doppler effect and was predicted by relativity. In 2010 time dilation was observed at speeds of less than 10 meters per second using optical atomic clocks connected by 75 meters of optical fiber.[22] Moving particles Main article: Experimental testing of time dilation A comparison of muon lifetimes at different speeds is possible. In the laboratory, slow muons are produced; and in the atmosphere, very fast moving muons are introduced by cosmic rays. Taking the muon lifetime at rest as the laboratory value of 2.197 ?s, the lifetime of a cosmic ray produced muon traveling at 98% of the speed of light is about five times longer, in agreement with observations. An example is Rossi and Hall (1941), who compared the population of cosmic-ray-produced muons at the top of a mountain to that observed at sea level.[23] The lifetime of particles produced in particle accelerators appears longer due to time dilation. In such experiments the "clock" is the time taken by processes leading to muon decay, and these processes take place in the moving muon at its own "clock rate", which is much slower than the laboratory clock. This is routinely taken into account in particle physics, and many dedicated measurements have been performed. For instance, in the muon storage ring at CERN the lifetime of muons circulating with ? = 29.327 was found to be dilated to 64.378 ?s, confirming time dilation to an accuracy of 0.9 ± 0.4 parts per thousand.[24] Proper time and Minkowski diagram Minkowski diagram and twin paradox

Clock C in relative motion between two synchronized clocks A and B. C meets A at d, and B at f.

Twin paradox. One twin has to change frames, leading to different proper times in the twin's world lines. In the Minkowski diagram from the first image on the right, clock C resting in inertial frame S? meets clock A at d and clock B at f (both resting in S). All three clocks simultaneously start to tick in S. The worldline of A is the ct-axis, the worldline of B intersecting f is parallel to the ct-axis, and the worldline of C is the ct?-axis. All events simultaneous with d in S are on the x-axis, in S? on the x?-axis.

The proper time between two events is indicated by a clock present at both events.[25] It is invariant, i.e., in all inertial frames it is agreed that this time is indicated by that clock. Interval df is therefore the proper time of clock C, and is shorter with respect to the coordinate times ef=dg of clocks B and A in S. Conversely, also proper time ef of B is shorter with respect to time if in S?, because event e was measured in S? already at time i due to relativity of simultaneity, long before C started to tick.

From that it can be seen, that the proper time between two events indicated by an unaccelerated clock present at both events, compared with the synchronized coordinate time measured in all other inertial frames, is always the minimal time interval between those events. However, the interval between two events can also correspond to the proper time of accelerated clocks present at both events. Under all possible proper times between two events, the proper time of the unaccelerated clock is maximal, which is the solution to the twin paradox.[25]

Derivation and formulation

Lorentz factor as a function of speed (in natural units where c = 1). Notice that for small speeds (less than 0.1), ? is approximately 1. In addition to the light clock used above, the formula for time dilation can be more generally derived from the temporal part of the Lorentz transformation.[26] Let there be two events at which the moving clock indicates {displaystyle t_{a}}{displaystyle t_{a}} and {displaystyle t_{b}}{displaystyle t_{b}}, thus

{displaystyle t_{a}^{prime }={frac {t_{a}-{frac {vx_{a}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}, t_{b}^{prime }={frac {t_{b}-{frac {vx_{b}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}}{displaystyle t_{a}^{prime }={frac {t_{a}-{frac {vx_{a}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}, t_{b}^{prime }={frac {t_{b}-{frac {vx_{b}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}}. Since the clock remains at rest in its inertial frame, it follows {displaystyle x_{a}=x_{b}}{displaystyle x_{a}=x_{b}}, thus the interval {displaystyle Delta t^{prime }=t_{b}^{prime }-t_{a}^{prime }}{displaystyle Delta t^{prime }=t_{b}^{prime }-t_{a}^{prime }} is given by

{displaystyle Delta t'=gamma ,Delta t={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},}Delta t'=gamma ,Delta t={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}, where ?t is the time interval between two co-local events (i.e. happening at the same place) for an observer in some inertial frame (e.g. ticks on his clock), known as the proper time, ?t? is the time interval between those same events, as measured by another observer, inertially moving with velocity v with respect to the former observer, v is the relative velocity between the observer and the moving clock, c is the speed of light, and the Lorentz factor (conventionally denoted by the Greek letter gamma or ?) is

{displaystyle gamma ={frac {1}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},.}gamma ={frac {1}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},. Thus the duration of the clock cycle of a moving clock is found to be increased: it is measured to be "running slow". The range of such variances in ordinary life, where v ? c, even considering space travel, are not great enough to produce easily detectable time dilation effects and such vanishingly small effects can be safely ignored for most purposes. It is only when an object approaches speeds on the order of 30,000 km/s (1/10 the speed of light) that time dilation becomes important.[27]

Hyperbolic motion Main article: Hyperbolic motion (relativity) In special relativity, time dilation is most simply described in circumstances where relative velocity is unchanging. Nevertheless, the Lorentz equations allow one to calculate proper time and movement in space for the simple case of a spaceship which is applied with a force per unit mass, relative to some reference object in uniform (i.e. constant velocity) motion, equal to g throughout the period of measurement.

Let t be the time in an inertial frame subsequently called the rest frame. Let x be a spatial coordinate, and let the direction of the constant acceleration as well as the spaceship's velocity (relative to the rest frame) be parallel to the x-axis. Assuming the spaceship's position at time t = 0 being x = 0 and the velocity being v0 and defining the following abbreviation

{displaystyle gamma _{0}={frac {1}{sqrt {1-v_{0}^{2}/c^{2}}}},}gamma _{0}={frac {1}{sqrt {1-v_{0}^{2}/c^{2}}}}, the following formulas hold:[28]

Position:

{displaystyle x(t)={frac {c^{2}}{g}}left({sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}-gamma _{0}right).}x(t)={frac {c^{2}}{g}}left({sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}-gamma _{0}right). Velocity:

{displaystyle v(t)={frac {gt+v_{0}gamma _{0}}{sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}}.}v(t)={frac {gt+v_{0}gamma _{0}}{sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}}. Proper time as function of coordinate time:

{displaystyle tau (t)=tau _{0}+int _{0}^{t}{sqrt {1-left({frac {v(t')}{c}}right)^{2}}}dt'.}tau (t)=tau _{0}+int _{0}^{t}{sqrt {1-left({frac {v(t')}{c}}right)^{2}}}dt'. In the case where v(0) = v0 = 0 and ?(0) = ?0 = 0 the integral can be expressed as a logarithmic function or, equivalently, as an inverse hyperbolic function:

{displaystyle tau (t)={frac {c}{g}}ln left({frac {gt}{c}}+{sqrt {1+left({frac {gt}{c}}right)^{2}}}right)={frac {c}{g}}operatorname {arsinh} left({frac {gt}{c}}right).}tau (t)={frac {c}{g}}ln left({frac {gt}{c}}+{sqrt {1+left({frac {gt}{c}}right)^{2}}}right)={frac {c}{g}}operatorname {arsinh} left({frac {gt}{c}}right). As functions of the proper time {displaystyle tau }tau of the ship, the following formulae hold:[29]

Position:

{displaystyle x(tau )={frac {c^{2}}{g}}left(cosh {frac {gtau }{c}}-1right).}{displaystyle x(tau )={frac {c^{2}}{g}}left(cosh {frac {gtau }{c}}-1right).} Velocity:

{displaystyle v(tau )=ctanh {frac {gtau }{c}}.}{displaystyle v(tau )=ctanh {frac {gtau }{c}}.} Coordinate time as function of proper time:

{displaystyle t(tau )={frac {c}{g}}sinh {frac {gtau }{c}}.}{displaystyle t(tau )={frac {c}{g}}sinh {frac {gtau }{c}}.} Clock hypothesis The clock hypothesis is the assumption that the rate at which a clock is affected by time dilation does not depend on its acceleration but only on its instantaneous velocity. This is equivalent to stating that a clock moving along a path {displaystyle P}P measures the proper time, defined by:

{displaystyle dtau =int _{P}{sqrt {dt^{2}-dx^{2}/c^{2}-dy^{2}/c^{2}-dz^{2}/c^{2}}}}dtau =int _{P}{sqrt {dt^{2}-dx^{2}/c^{2}-dy^{2}/c^{2}-dz^{2}/c^{2}}}. The clock hypothesis was implicitly (but not explicitly) included in Einstein's original 1905 formulation of special relativity. Since then, it has become a standard assumption and is usually included in the axioms of special relativity, especially in the light of experimental verification up to very high accelerations in particle accelerators.[30][31]

Gravitational time dilation Main article: Gravitational time dilation

Time passes more quickly further from a center of gravity, as is witnessed with massive objects (like the Earth) Gravitational time dilation is experienced by an observer that, at a certain altitude within a gravitational potential well, finds that his local clocks measure less elapsed time than identical clocks situated at higher altitude (and which are therefore at higher gravitational potential).

Gravitational time dilation is at play e.g. for ISS astronauts. While the astronauts' relative velocity slows down their time, the reduced gravitational influence at their location speeds it up, although at a lesser degree. Also, a climber's time is theoretically passing slightly faster at the top of a mountain compared to people at sea level. It has also been calculated that due to time dilation, the core of the Earth is 2.5 years younger than the crust.[32] "A clock used to time a full rotation of the earth will measure the day to be approximately an extra 10 ns/day longer for every km of altitude above the reference geoid."[33] Travel to regions of space where extreme gravitational time dilation is taking place, such as near a black hole, could yield time-shifting results analogous to those of near-lightspeed space travel.

Contrarily to velocity time dilation, in which both observers measure the other as aging slower (a reciprocal effect), gravitational time dilation is not reciprocal. This means that with gravitational time dilation both observers agree that the clock nearer the center of the gravitational field is slower in rate, and they agree on the ratio of the difference.

Experimental testing Main article: Experimental testing of time dilation In 1959 Robert Pound and Glen A. Rebka measured the very slight gravitational redshift in the frequency of light emitted at a lower height, where Earth's gravitational field is relatively more intense. The results were within 10% of the predictions of general relativity. In 1964, Pound and J. L. Snider measured a result within 1% of the value predicted by gravitational time dilation.[34] (See Pound–Rebka experiment) In 2010 gravitational time dilation was measured at the earth's surface with a height difference of only one meter, using optical atomic clocks.[22] Combined effect of velocity and gravitational time dilation

Daily time dilation (gain or loss if negative) in microseconds as a function of (circular) orbit radius r = rs/re, where rs is satellite orbit radius and re is the equatorial Earth radius, calculated using the Schwarzschild metric. At r ? 1.497[Note 1] there is no time dilation. Here the effects of motion and reduced gravity cancel. ISS astronauts fly below, whereas GPS and geostationary satellites fly above.[1]

Daily time dilation over circular orbit height split into its components High-accuracy timekeeping, low-Earth-orbit satellite tracking, and pulsar timing are applications that require the consideration of the combined effects of mass and motion in producing time dilation. Practical examples include the International Atomic Time standard and its relationship with the Barycentric Coordinate Time standard used for interplanetary objects.

Relativistic time dilation effects for the solar system and the earth can be modeled very precisely by the Schwarzschild solution to the Einstein field equations. In the Schwarzschild metric, the interval {displaystyle dt_{text{E}}}{displaystyle dt_{text{E}}} is given by[36][37]

{displaystyle dt_{text{E}}^{2}=left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)dt_{text{c}}^{2}-left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)^{-1}{frac {dx^{2}+dy^{2}+dz^{2}}{c^{2}}},}dt_{text{E}}^{2}=left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)dt_{text{c}}^{2}-left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)^{-1}{frac {dx^{2}+dy^{2}+dz^{2}}{c^{2}}}, where

{displaystyle dt_{text{E}}}{displaystyle dt_{text{E}}} is a small increment of proper time {displaystyle t_{text{E}}}{displaystyle t_{text{E}}} (an interval that could be recorded on an atomic clock), {displaystyle dt_{text{c}}}{displaystyle dt_{text{c}}} is a small increment in the coordinate {displaystyle t_{text{c}}}{displaystyle t_{text{c}}} (coordinate time), {displaystyle dx,dy,dz}{displaystyle dx,dy,dz} are small increments in the three coordinates {displaystyle x,y,z}x, y, z of the clock's position, {displaystyle {frac {GM_{i}}{r_{i}}}}{displaystyle {frac {GM_{i}}{r_{i}}}} represents the sum of the Newtonian gravitational potentials due to the masses in the neighborhood, based on their distances {displaystyle r_{i}}r_{i} from the clock. This sum includes any tidal potentials. The coordinate velocity of the clock is given by

{displaystyle v^{2}={frac {dx^{2}+dy^{2}+dz^{2}}{dt_{text{c}}^{2}}}.,}v^{2}={frac {dx^{2}+dy^{2}+dz^{2}}{dt_{text{c}}^{2}}}., The coordinate time {displaystyle t_{c}}t_c is the time that would be read on a hypothetical "coordinate clock" situated infinitely far from all gravitational masses ({displaystyle U=0}U=0), and stationary in the system of coordinates ({displaystyle v=0}v=0). The exact relation between the rate of proper time and the rate of coordinate time for a clock with a radial component of velocity is

{displaystyle {frac {dt_{text{E}}}{dt_{text{c}}}}={sqrt {1-{frac {2U}{c^{2}}}-{frac {v^{2}}{c^{2}}}-left({frac {c^{2}}{2U}}-1right)^{-1}{frac {{v_{shortparallel }}^{2}}{c^{2}}}}}={sqrt {1-left(beta ^{2}+beta _{e}^{2}+{frac {beta _{shortparallel }^{2}beta _{e}^{2}}{1-beta _{e}^{2}}}right)}},}{displaystyle {frac {dt_{text{E}}}{dt_{text{c}}}}={sqrt {1-{frac {2U}{c^{2}}}-{frac {v^{2}}{c^{2}}}-left({frac {c^{2}}{2U}}-1right)^{-1}{frac {{v_{shortparallel }}^{2}}{c^{2}}}}}={sqrt {1-left(beta ^{2}+beta _{e}^{2}+{frac {beta _{shortparallel }^{2}beta _{e}^{2}}{1-beta _{e}^{2}}}right)}},} where

{displaystyle v_{shortparallel }}{displaystyle v_{shortparallel }} is the radial velocity, {displaystyle v_{e}={sqrt {frac {2GM_{i}}{r_{i}}}}}{displaystyle v_{e}={sqrt {frac {2GM_{i}}{r_{i}}}}} is the escape velocity, {displaystyle beta =v/c}beta = v/c, {displaystyle beta _{e}=v_{e}/c}{displaystyle beta _{e}=v_{e}/c} and {displaystyle beta _{shortparallel }=v_{shortparallel }/c}{displaystyle beta _{shortparallel }=v_{shortparallel }/c} are velocities as a percentage of speed of light c, {displaystyle U={frac {GM_{i}}{r_{i}}}}{displaystyle U={frac {GM_{i}}{r_{i}}}} is the Newtonian potential, equivalent to half of the escape velocity squared. The above equation is exact under the assumptions of the Schwarzschild solution. It reduces to velocity time dilation equation in the presence of motion and absence of gravity, i.e. {displaystyle beta _{e}=0}{displaystyle beta _{e}=0}. It reduces to gravitational time dilation equation in the absence of motion and presence of gravity, i.e. {displaystyle beta =0=beta _{shortparallel }}{displaystyle beta =0=beta _{shortparallel }}.

Experimental testing Hafele and Keating, in 1971, flew caesium atomic clocks east and west around the Earth in commercial airliners, to compare the elapsed time against that of a clock that remained at the U.S. Naval Observatory. Two opposite effects came into play. The clocks were expected to age more quickly (show a larger elapsed time) than the reference clock, since they were in a higher (weaker) gravitational potential for most of the trip (c.f. Pound–Rebka experiment). But also, contrastingly, the moving clocks were expected to age more slowly because of the speed of their travel. From the actual flight paths of each trip, the theory predicted that the flying clocks, compared with reference clocks at the U.S. Naval Observatory, should have lost 40±23 nanoseconds during the eastward trip and should have gained 275±21 nanoseconds during the westward trip. Relative to the atomic time scale of the U.S. Naval Observatory, the flying clocks lost 59±10 nanoseconds during the eastward trip and gained 273±7 nanoseconds during the westward trip (where the error bars represent standard deviation).[38] In 2005, the National Physical Laboratory in the United Kingdom reported their limited replication of this experiment.[39] The NPL experiment differed from the original in that the caesium clocks were sent on a shorter trip (London–Washington, D.C. return), but the clocks were more accurate. The reported results are within 4% of the predictions of relativity, within the uncertainty of the measurements. The Global Positioning System can be considered a continuously operating experiment in both special and general relativity. The in-orbit clocks are corrected for both special and general relativistic time dilation effects as described above, so that (as observed from the earth's surface) they run at the same rate as clocks on the surface of the Earth.[40] icon Physics portal See also Length contraction Mass in special relativity Footnotes Average time dilation has a weak dependence on the orbital inclination angle (Ashby 2003, p.32). The r ? 1.497 result corresponds to[35] the orbital inclination of modern GPS satellites, which is 55 degrees. References Ashby, Neil (2003). "Relativity in the Global Positioning System" (PDF). Living Reviews in Relativity. 6 (1): 16. Bibcode:2003LRR.....6....1A. doi:10.12942/lrr-2003-1. PMC 5253894. PMID 28163638. Lu, Ed. "Expedition 7: Relativity". Ed's Musing from Space. NASA. Retrieved 2018-04-08. "Is time travel possible?". NASA Space Place. Retrieved 2018-08-03. Miller, Arthur I. (1981). Albert Einstein's Special Theory of Relativity: Emergence (1905) and Early Interpretation (1905–1911). Reading, Massachusetts: Addison–Wesley. ISBN 978-0-201-04679-3.. Darrigol, Olivier (2005). The Genesis of the Theory of Relativity (PDF). Séminaire Poincaré. 1. pp. 1–22. doi:10.1007/3-7643-7436-5_1. ISBN 978-3-7643-7435-8. Larmor, Joseph (1897). "On a Dynamical Theory of the Electric and Luminiferous Medium, Part 3, Relations with Material Media" . Philosophical Transactions of the Royal Society. 190: 205–300. Bibcode:1897RSPTA.190..205L. doi:10.1098/rsta.1897.0020. Cohn, Emil (1904), "Zur Elektrodynamik bewegter Systeme II" [On the Electrodynamics of Moving Systems II], Sitzungsberichte der Königlich Preussischen Akademie der Wissenschaften, 1904/2 (43): 1404–1416 Einstein, Albert (1905). "Zur Elektrodynamik bewegter Körper". Annalen der Physik. 322 (10): 891–921. Bibcode:1905AnP...322..891E. doi:10.1002/andp.19053221004.. See also: English translation. Minkowski, Hermann (1908) [1907], "Die Grundgleichungen für die elektromagnetischen Vorgänge in bewegten Körpern" [The Fundamental Equations for Electromagnetic Processes in Moving Bodies], Nachrichten von der Gesellschaft der Wissenschaften zu Göttingen, Mathematisch-Physikalische Klasse: 53–111 Hraskó, Péter (2011). Basic Relativity: An Introductory Essay (illustrated ed.). Springer Science & Business Media. p. 60. ISBN 978-3-642-17810-8. Extract of page 60 Calder, Nigel (2006). Magic Universe: A grand tour of modern science. Oxford University Press. p. 378. ISBN 978-0-19-280669-7. Overbye, Dennis (2005-06-28). "A Trip Forward in Time. Your Travel Agent: Einstein". The New York Times. Retrieved 2015-12-08. Gott, J., Richard (2002). Time Travel in Einstein's Universe. p. 75. Cassidy, David C.; Holton, Gerald James; Rutherford, Floyd James (2002). Understanding Physics. Springer-Verlag. p. 422. ISBN 978-0-387-98756-9. Cutner, Mark Leslie (2003). Astronomy, A Physical Perspective. Cambridge University Press. p. 128. ISBN 978-0-521-82196-4. Lerner, Lawrence S. (1996). Physics for Scientists and Engineers, Volume 2. Jones and Bartlett. pp. 1051–1052. ISBN 978-0-7637-0460-5. Ellis, George F. R.; Williams, Ruth M. (2000). Flat and Curved Space-times (2n ed.). Oxford University Press. pp. 28–29. ISBN 978-0-19-850657-7. Adams, Steve (1997). Relativity: An introduction to space-time physics. CRC Press. p. 54. ISBN 978-0-7484-0621-0. Blaszczak, Z. (2007). Laser 2006. Springer. p. 59. ISBN 978-3540711131. Hasselkamp, D.; Mondry, E.; Scharmann, A. (1979). "Direct observation of the transversal Doppler-shift". Zeitschrift für Physik A. 289 (2): 151–155. Bibcode:1979ZPhyA.289..151H. doi:10.1007/BF01435932. Einstein, A. (1905). "On the electrodynamics of moving bodies". Fourmilab. Chou, C. W.; Hume, D. B.; Rosenband, T.; Wineland, D. J. (2010). "Optical Clocks and Relativity". Science. 329 (5999): 1630–1633. Bibcode:2010Sci...329.1630C. doi:10.1126/science.1192720. PMID 20929843. Stewart, J. V. (2001). Intermediate electromagnetic theory. World Scientific. p. 705. ISBN 978-981-02-4470-5. Bailey, J. et al. Nature 268, 301 (1977) Edwin F. Taylor, John Archibald Wheeler (1992). Spacetime Physics: Introduction to Special Relativity. New York: W. H. Freeman. ISBN 978-0-7167-2327-1. Born, Max (1964), Einstein's Theory of Relativity, Dover Publications, ISBN 978-0-486-60769-6 Petkov, Vesselin (2009). Relativity and the Nature of Spacetime (2nd, illustrated ed.). Springer Science & Business Media. p. 87. ISBN 978-3-642-01962-3. Extract of page 87 See equations 3, 4, 6 and 9 of Iorio, Lorenzo (2005). "An analytical treatment of the Clock Paradox in the framework of the Special and General Theories of Relativity". Foundations of Physics Letters. 18 (1): 1–19. arXiv:physics/0405038. Bibcode:2005FoPhL..18....1I. doi:10.1007/s10702-005-2466-8. Rindler, W. (1977). Essential Relativity. Springer. pp. 49–50. ISBN 978-3540079705. Bailey, H.; Borer, K.; Combley F.; Drumm H.; Krienen F.; Lange F.; Picasso E.; Ruden W. von; Farley F. J. M.; Field J. H.; Flegel W. & Hattersley P. M. (1977). "Measurements of relativistic time dilatation for positive and negative muons in a circular orbit". Nature. 268 (5618): 301–305. Bibcode:1977Natur.268..301B. doi:10.1038/268301a0. Roos, C. E.; Marraffino, J.; Reucroft, S.; Waters, J.; Webster, M. S.; Williams, E. G. H. (1980). "?+/- lifetimes and longitudinal acceleration". Nature. 286 (5770): 244–245. Bibcode:1980Natur.286..244R. doi:10.1038/286244a0. "New calculations show Earth's core is much younger than thought". Phys.org. 26 May 2016. Burns, M. Shane; Leveille, Michael D.; Dominguez, Armand R.; Gebhard, Brian B.; Huestis, Samuel E.; Steele, Jeffrey; Patterson, Brian; Sell, Jerry F.; Serna, Mario; Gearba, M. Alina; Olesen, Robert; O'Shea, Patrick; Schiller, Jonathan (18 September 2017). "Measurement of gravitational time dilation: An undergraduate research project". American Journal of Physics. 85 (10): 757–762. arXiv:1707.00171. doi:10.1119/1.5000802. Pound, R. V.; Snider J. L. (November 2, 1964). "Effect of Gravity on Nuclear Resonance". Physical Review Letters. 13 (18): 539–540. Bibcode:1964PhRvL..13..539P. doi:10.1103/PhysRevLett.13.539. Ashby, Neil (2002). "Relativity in the Global Positioning System". Physics Today. 55 (5): 45. Bibcode:2002PhT....55e..41A. doi:10.1063/1.1485583. See equations 2 & 3 (combined here and divided throughout by c2) at pp. 35–36 in Moyer, T. D. (1981). "Transformation from proper time on Earth to coordinate time in solar system barycentric space-time frame of reference". Celestial Mechanics. 23 (1): 33–56. Bibcode:1981CeMec..23...33M. doi:10.1007/BF01228543. hdl:2060/19770007221. A version of the same relationship can also be seen at equation 2 in Ashbey, Neil (2002). "Relativity and the Global Positioning System" (PDF). Physics Today. 55 (5): 45. Bibcode:2002PhT....55e..41A. doi:10.1063/1.1485583. Nave, C. R. (22 August 2005). "Hafele and Keating Experiment". HyperPhysics. Retrieved 2013-08-05. "Einstein" (PDF). Metromnia. National Physical Laboratory. 2005. pp. 1–4. Kaplan, Elliott; Hegarty, Christopher (2005). Understanding GPS: Principles and Applications. Artech House. p. 306. ISBN 978-1-58053-895-4. Extract of page 306 Further reading Callender, C.; Edney, R. (2001). Introducing Time. Icon Books. ISBN 978-1-84046-592-1. Einstein, A. (1905). "Zur Elektrodynamik bewegter Körper". Annalen der Physik. 322 (10): 891. Bibcode:1905AnP...322..891E. doi:10.1002/andp.19053221004. Einstein, A. (1907). "Über die Möglichkeit einer neuen Prüfung des Relativitätsprinzips". Annalen der Physik. 328 (6): 197–198. Bibcode:1907AnP...328..197E. doi:10.1002/andp.19073280613. Hasselkamp, D.; Mondry, E.; Scharmann, A. (1979). "Direct Observation of the Transversal Doppler-Shift". Zeitschrift für Physik A. 289 (2): 151–155. Bibcode:1979ZPhyA.289..151H. doi:10.1007/BF01435932. Ives, H. E.; Stilwell, G. R. (1938). "An experimental study of the rate of a moving clock". Journal of the Optical Society of America. 28 (7): 215–226. doi:10.1364/JOSA.28.000215. Ives, H. E.; Stilwell, G. R. (1941). "An experimental study of the rate of a moving clock. II". Journal of the Optical Society of America. 31 (5): 369–374. doi:10.1364/JOSA.31.000369. Joos, G. (1959). "Bewegte Bezugssysteme in der Akustik. Der Doppler-Effekt". Lehrbuch der Theoretischen Physik, Zweites Buch (11th ed.). Larmor, J. (1897). "On a dynamical theory of the electric and luminiferous medium". Philosophical Transactions of the Royal Society. 190: 205–300. Bibcode:1897RSPTA.190..205L. doi:10.1098/rsta.1897.0020. (third and last in a series of papers with the same name). Poincaré, H. (1900). "La théorie de Lorentz et le principe de Réaction". Archives Néerlandaises. 5: 253–78. Puri, A. (2015). "Einstein versus the simple pendulum formula: does gravity slow all clocks?". Physics Education. 50 (4): 431. Bibcode:2015PhyEd..50..431P. doi:10.1088/0031-9120/50/4/431. Reinhardt, S.; et al. (2007). "Test of relativistic time dilation with fast optical atomic clocks at different velocities" (PDF). Nature Physics. 3 (12): 861–864. Bibcode:2007NatPh...3..861R. doi:10.1038/nphys778. Archived from the original (PDF) on 2009-07-12. Rossi, B.; Hall, D. B. (1941). "Variation of the Rate of Decay of Mesotrons with Momentum". Physical Review. 59 (3): 223. Bibcode:1941PhRv...59..223R. doi:10.1103/PhysRev.59.223. Weiss, M. "Two way time transfer for satellites". National Institute of Standards and Technology. Archived from the original on 2017-05-29. Voigt, W. (1887). "Über das Doppler'sche princip". Nachrichten von der Königlicher Gesellschaft der Wissenschaften zu Göttingen. 2: 41–51. External links Merrifield, Michael. "Lorentz Factor (and time dilation)". Sixty Symbols. Brady Haran for the University of Nottingham. vte Time vte Time measurement and standards vte Relativity Categories: Special relativityTime in physicsConcepts in physics Navigation menu Not logged inTalkContributionsCreate accountLog inArticleTalkReadEditView historySearch Search Wikipedia Main page Contents Featured content Current events Random article Donate to Wikipedia Wikipedia store Interaction Help About Wikipedia Community portal Recent changes Contact page Tools What links here Related changes Upload file Special pages Permanent link Page information Wikidata item Cite this page In other projects Wikimedia Commons Print/export Download as PDF Printable version

Languages ??????? Español Bahasa Indonesia Bahasa Melayu Português ??????? ?????????? ???? ?? 37 more Edit links This page was last edited on 11 January 2020, at 10:05 (UTC). Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-pro

View Details

https://www.youtube.com/watch?v=uVjBB3K-Na4 Time dilation From Wikipedia, the free encyclopedia Jump to navigationJump to search

Time dilation explains why two working clocks will report different times after different accelerations. For example, at the ISS time goes slower, lagging 0.007 seconds behind for every six months. For GPS satellites to work, they must adjust for similar bending of spacetime to coordinate with systems on Earth.[1] Time dilation is a difference in the elapsed time measured by two clocks, either due to them having a velocity relative to each other, or by there being a gravitational potential difference between their locations. After compensating for varying signal delays due to the changing distance between an observer and a moving clock (i.e. Doppler effect), the observer will measure the moving clock as ticking slower than a clock that is at rest in the observer's own reference frame. A clock that is close to a massive body (and which therefore is at lower gravitational potential) will record less elapsed time than a clock situated further from the said massive body (and which is at a higher gravitational potential).

These predictions of the theory of relativity have been repeatedly confirmed by experiment, and they are of practical concern, for instance in the operation of satellite navigation systems such as GPS and Galileo.[1][2] Time dilation has also been the subject of science fiction works, as it technically provides the means for forward time travel.[3]

Contents 1 History 2 Velocity time dilation 2.1 Simple inference of velocity time dilation 2.2 Reciprocity 2.3 Experimental testing 2.3.1 Doppler effect 2.3.2 Moving particles 2.4 Proper time and Minkowski diagram 2.5 Derivation and formulation 2.6 Hyperbolic motion 2.7 Clock hypothesis 3 Gravitational time dilation 3.1 Experimental testing 4 Combined effect of velocity and gravitational time dilation 4.1 Experimental testing 5 See also 6 Footnotes 7 References 8 Further reading 9 External links History Main article: History of special relativity Time dilation by the Lorentz factor was predicted by several authors at the turn of the 20th century.[4][5] Joseph Larmor (1897), at least for electrons orbiting a nucleus, wrote "... individual electrons describe corresponding parts of their orbits in times shorter for the [rest] system in the ratio :{displaystyle scriptstyle {sqrt {1-{frac {v^{2}}{c^{2}}}}}}scriptstyle {sqrt {1-{frac {v^{2}}{c^{2}}}}}".[6] Emil Cohn (1904) specifically related this formula to the rate of clocks.[7] In the context of special relativity it was shown by Albert Einstein (1905) that this effect concerns the nature of time itself, and he was also the first to point out its reciprocity or symmetry.[8] Subsequently, Hermann Minkowski (1907) introduced the concept of proper time which further clarified the meaning of time dilation.[9]

Velocity time dilation

From the local frame of reference of the blue clock, the red clock, being in motion, is perceived as ticking slower[10] (Exaggerated) Special relativity indicates that, for an observer in an inertial frame of reference, a clock that is moving relative to him will be measured to tick slower than a clock that is at rest in his frame of reference. This case is sometimes called special relativistic time dilation. The faster the relative velocity, the greater the time dilation between one another, with the rate of time reaching zero as one approaches the speed of light (299,792,458 m/s). This causes massless particles that travel at the speed of light to be unaffected by the passage of time.

Theoretically, time dilation would make it possible for passengers in a fast-moving vehicle to advance further into the future in a short period of their own time. For sufficiently high speeds, the effect is dramatic. For example, one year of travel might correspond to ten years on Earth. Indeed, a constant 1 g acceleration would permit humans to travel through the entire known Universe in one human lifetime.[11]

With current technology severely limiting the velocity of space travel, however, the differences experienced in practice are minuscule: after 6 months on the International Space Station (ISS) (which orbits Earth at a speed of about 7,700 m/s[2]) an astronaut would have aged about 0.007 seconds less than those on Earth. The cosmonauts Sergei Krikalev and Sergei Avdeyev both experienced time dilation of about 20 milliseconds compared to time that passed on Earth.[12][13]

Simple inference of velocity time dilation

Left: Observer at rest measures time 2L/c between co-local events of light signal generation at A and arrival at A. Right: Events according to an observer moving to the left of the setup: bottom mirror A when signal is generated at time t'=0, top mirror B when signal gets reflected at time t'=D/c, bottom mirror A when signal returns at time t'=2D/c Time dilation can be inferred from the observed constancy of the speed of light in all reference frames dictated by the second postulate of special relativity.[14][15][16][17]

This constancy of the speed of light means that, counter to intuition, speeds of material objects and light are not additive. It is not possible to make the speed of light appear greater by moving towards or away from the light source.

Consider then, a simple clock consisting of two mirrors A and B, between which a light pulse is bouncing. The separation of the mirrors is L and the clock ticks once each time the light pulse hits either of the mirrors.

In the frame in which the clock is at rest (diagram on the left), the light pulse traces out a path of length 2L and the period of the clock is 2L divided by the speed of light:

{displaystyle Delta t={frac {2L}{c}}.}Delta t={frac {2L}{c}}. From the frame of reference of a moving observer traveling at the speed v relative to the resting frame of the clock (diagram at right), the light pulse is seen as tracing out a longer, angled path. Keeping the speed of light constant for all inertial observers, requires a lengthening of the period of this clock from the moving observer's perspective. That is to say, in a frame moving relative to the local clock, this clock will appear to be running more slowly. Straightforward application of the Pythagorean theorem leads to the well-known prediction of special relativity:

The total time for the light pulse to trace its path is given by

{displaystyle Delta t'={frac {2D}{c}}.}Delta t'={frac {2D}{c}}. The length of the half path can be calculated as a function of known quantities as

{displaystyle D={sqrt {left({frac {1}{2}}vDelta t'right)^{2}+L^{2}}}.}{displaystyle D={sqrt {left({frac {1}{2}}vDelta t'right)^{2}+L^{2}}}.} Elimination of the variables D and L from these three equations results in

{displaystyle Delta t'={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},}{displaystyle Delta t'={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},} which expresses the fact that the moving observer's period of the clock {displaystyle Delta t'}Delta t' is longer than the period {displaystyle Delta t}Delta t in the frame of the clock itself.

Reciprocity

Time UV of a clock in S is shorter compared to Ux? in S?, and time UW of a clock in S? is shorter compared to Ux in S

Transversal time dilation. The blue dots represent a pulse of light. Each pair of dots with light "bouncing" between them is a clock. For each group of clocks, the other group appears to be ticking more slowly, because the moving clock's light pulse has to travel a larger distance than the stationary clock's light pulse. That is so, even though the clocks are identical and their relative motion is perfectly reciprocal. Given a certain frame of reference, and the "stationary" observer described earlier, if a second observer accompanied the "moving" clock, each of the observers would perceive the other's clock as ticking at a slower rate than their own local clock, due to them both perceiving the other to be the one that's in motion relative to their own stationary frame of reference.

Common sense would dictate that, if the passage of time has slowed for a moving object, said object would observe the external world's time to be correspondingly sped up. Counterintuitively, special relativity predicts the opposite. When two observers are in motion relative to each other, each will measure the other's clock slowing down, in concordance with them being moving relative to the observer's frame of reference.

While this seems self-contradictory, a similar oddity occurs in everyday life. If two persons A and B observe each other from a distance, B will appear small to A, but at the same time A will appear small to B. Being familiar with the effects of perspective, there is no contradiction or paradox in this situation.[18]

The reciprocity of the phenomenon also leads to the so-called twin paradox where the aging of twins, one staying on Earth and the other embarking on a space travel, is compared, and where the reciprocity suggests that both persons should have the same age when they reunite. On the contrary, at the end of the round-trip, the traveling twin will be younger than his brother on Earth. The dilemma posed by the paradox, however, can be explained by the fact that the traveling twin must markedly accelerate in at least three phases of the trip (beginning, direction change, and end), while the other will only experience negligible acceleration, due to rotation and revolution of Earth. During the acceleration phases of the space travel, time dilation is not symmetric.

Experimental testing See also: Tests of special relativity Doppler effect Main article: Ives–Stilwell experiment The stated purpose by Ives and Stilwell (1938, 1941) of these experiments was to verify the time dilation effect, predicted by Larmor–Lorentz ether theory, due to motion through the ether using Einstein's suggestion that Doppler effect in canal rays would provide a suitable experiment. These experiments measured the Doppler shift of the radiation emitted from cathode rays, when viewed from directly in front and from directly behind. The high and low frequencies detected were not the classically predicted values {displaystyle {frac {f_{0}}{1-v/c}}qquad {text{and}}qquad {frac {f_{0}}{1+v/c}}.,}{frac {f_{0}}{1-v/c}}qquad {text{and}}qquad {frac {f_{0}}{1+v/c}}., The high and low frequencies of the radiation from the moving sources were measured as[19] {displaystyle {sqrt {frac {1+v/c}{1-v/c}}}f_{0}=gamma left(1+v/cright)f_{0}qquad {text{and}}qquad {sqrt {frac {1-v/c}{1+v/c}}}f_{0}=gamma left(1-v/cright)f_{0},,}{sqrt {frac {1+v/c}{1-v/c}}}f_{0}=gamma left(1+v/cright)f_{0}qquad {text{and}}qquad {sqrt {frac {1-v/c}{1+v/c}}}f_{0}=gamma left(1-v/cright)f_{0},, as deduced by Einstein (1905) from the Lorentz transformation, when the source is running slow by the Lorentz factor. Hasselkamp, Mondry, and Scharmann[20] (1979) measured the Doppler shift from a source moving at right angles to the line of sight. The most general relationship between frequencies of the radiation from the moving sources is given by: {displaystyle f_{mathrm {detected} }=f_{mathrm {rest} }{left(1-{frac {v}{c}}cos phi right)/{sqrt {1-{v^{2}}/{c^{2}}}}}}f_{mathrm {detected} }=f_{mathrm {rest} }{left(1-{frac {v}{c}}cos phi right)/{sqrt {1-{v^{2}}/{c^{2}}}}} as deduced by Einstein (1905).[21] For ? = 90° (cos ? = 0) this reduces to fdetected = frest?. This lower frequency from the moving source can be attributed to the time dilation effect and is often called the transverse Doppler effect and was predicted by relativity. In 2010 time dilation was observed at speeds of less than 10 meters per second using optical atomic clocks connected by 75 meters of optical fiber.[22] Moving particles Main article: Experimental testing of time dilation A comparison of muon lifetimes at different speeds is possible. In the laboratory, slow muons are produced; and in the atmosphere, very fast moving muons are introduced by cosmic rays. Taking the muon lifetime at rest as the laboratory value of 2.197 ?s, the lifetime of a cosmic ray produced muon traveling at 98% of the speed of light is about five times longer, in agreement with observations. An example is Rossi and Hall (1941), who compared the population of cosmic-ray-produced muons at the top of a mountain to that observed at sea level.[23] The lifetime of particles produced in particle accelerators appears longer due to time dilation. In such experiments the "clock" is the time taken by processes leading to muon decay, and these processes take place in the moving muon at its own "clock rate", which is much slower than the laboratory clock. This is routinely taken into account in particle physics, and many dedicated measurements have been performed. For instance, in the muon storage ring at CERN the lifetime of muons circulating with ? = 29.327 was found to be dilated to 64.378 ?s, confirming time dilation to an accuracy of 0.9 ± 0.4 parts per thousand.[24] Proper time and Minkowski diagram Minkowski diagram and twin paradox

Clock C in relative motion between two synchronized clocks A and B. C meets A at d, and B at f.

Twin paradox. One twin has to change frames, leading to different proper times in the twin's world lines. In the Minkowski diagram from the first image on the right, clock C resting in inertial frame S? meets clock A at d and clock B at f (both resting in S). All three clocks simultaneously start to tick in S. The worldline of A is the ct-axis, the worldline of B intersecting f is parallel to the ct-axis, and the worldline of C is the ct?-axis. All events simultaneous with d in S are on the x-axis, in S? on the x?-axis.

The proper time between two events is indicated by a clock present at both events.[25] It is invariant, i.e., in all inertial frames it is agreed that this time is indicated by that clock. Interval df is therefore the proper time of clock C, and is shorter with respect to the coordinate times ef=dg of clocks B and A in S. Conversely, also proper time ef of B is shorter with respect to time if in S?, because event e was measured in S? already at time i due to relativity of simultaneity, long before C started to tick.

From that it can be seen, that the proper time between two events indicated by an unaccelerated clock present at both events, compared with the synchronized coordinate time measured in all other inertial frames, is always the minimal time interval between those events. However, the interval between two events can also correspond to the proper time of accelerated clocks present at both events. Under all possible proper times between two events, the proper time of the unaccelerated clock is maximal, which is the solution to the twin paradox.[25]

Derivation and formulation

Lorentz factor as a function of speed (in natural units where c = 1). Notice that for small speeds (less than 0.1), ? is approximately 1. In addition to the light clock used above, the formula for time dilation can be more generally derived from the temporal part of the Lorentz transformation.[26] Let there be two events at which the moving clock indicates {displaystyle t_{a}}{displaystyle t_{a}} and {displaystyle t_{b}}{displaystyle t_{b}}, thus

{displaystyle t_{a}^{prime }={frac {t_{a}-{frac {vx_{a}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}, t_{b}^{prime }={frac {t_{b}-{frac {vx_{b}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}}{displaystyle t_{a}^{prime }={frac {t_{a}-{frac {vx_{a}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}, t_{b}^{prime }={frac {t_{b}-{frac {vx_{b}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}}. Since the clock remains at rest in its inertial frame, it follows {displaystyle x_{a}=x_{b}}{displaystyle x_{a}=x_{b}}, thus the interval {displaystyle Delta t^{prime }=t_{b}^{prime }-t_{a}^{prime }}{displaystyle Delta t^{prime }=t_{b}^{prime }-t_{a}^{prime }} is given by

{displaystyle Delta t'=gamma ,Delta t={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},}Delta t'=gamma ,Delta t={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}, where ?t is the time interval between two co-local events (i.e. happening at the same place) for an observer in some inertial frame (e.g. ticks on his clock), known as the proper time, ?t? is the time interval between those same events, as measured by another observer, inertially moving with velocity v with respect to the former observer, v is the relative velocity between the observer and the moving clock, c is the speed of light, and the Lorentz factor (conventionally denoted by the Greek letter gamma or ?) is

{displaystyle gamma ={frac {1}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},.}gamma ={frac {1}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},. Thus the duration of the clock cycle of a moving clock is found to be increased: it is measured to be "running slow". The range of such variances in ordinary life, where v ? c, even considering space travel, are not great enough to produce easily detectable time dilation effects and such vanishingly small effects can be safely ignored for most purposes. It is only when an object approaches speeds on the order of 30,000 km/s (1/10 the speed of light) that time dilation becomes important.[27]

Hyperbolic motion Main article: Hyperbolic motion (relativity) In special relativity, time dilation is most simply described in circumstances where relative velocity is unchanging. Nevertheless, the Lorentz equations allow one to calculate proper time and movement in space for the simple case of a spaceship which is applied with a force per unit mass, relative to some reference object in uniform (i.e. constant velocity) motion, equal to g throughout the period of measurement.

Let t be the time in an inertial frame subsequently called the rest frame. Let x be a spatial coordinate, and let the direction of the constant acceleration as well as the spaceship's velocity (relative to the rest frame) be parallel to the x-axis. Assuming the spaceship's position at time t = 0 being x = 0 and the velocity being v0 and defining the following abbreviation

{displaystyle gamma _{0}={frac {1}{sqrt {1-v_{0}^{2}/c^{2}}}},}gamma _{0}={frac {1}{sqrt {1-v_{0}^{2}/c^{2}}}}, the following formulas hold:[28]

Position:

{displaystyle x(t)={frac {c^{2}}{g}}left({sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}-gamma _{0}right).}x(t)={frac {c^{2}}{g}}left({sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}-gamma _{0}right). Velocity:

{displaystyle v(t)={frac {gt+v_{0}gamma _{0}}{sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}}.}v(t)={frac {gt+v_{0}gamma _{0}}{sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}}. Proper time as function of coordinate time:

{displaystyle tau (t)=tau _{0}+int _{0}^{t}{sqrt {1-left({frac {v(t')}{c}}right)^{2}}}dt'.}tau (t)=tau _{0}+int _{0}^{t}{sqrt {1-left({frac {v(t')}{c}}right)^{2}}}dt'. In the case where v(0) = v0 = 0 and ?(0) = ?0 = 0 the integral can be expressed as a logarithmic function or, equivalently, as an inverse hyperbolic function:

{displaystyle tau (t)={frac {c}{g}}ln left({frac {gt}{c}}+{sqrt {1+left({frac {gt}{c}}right)^{2}}}right)={frac {c}{g}}operatorname {arsinh} left({frac {gt}{c}}right).}tau (t)={frac {c}{g}}ln left({frac {gt}{c}}+{sqrt {1+left({frac {gt}{c}}right)^{2}}}right)={frac {c}{g}}operatorname {arsinh} left({frac {gt}{c}}right). As functions of the proper time {displaystyle tau }tau of the ship, the following formulae hold:[29]

Position:

{displaystyle x(tau )={frac {c^{2}}{g}}left(cosh {frac {gtau }{c}}-1right).}{displaystyle x(tau )={frac {c^{2}}{g}}left(cosh {frac {gtau }{c}}-1right).} Velocity:

{displaystyle v(tau )=ctanh {frac {gtau }{c}}.}{displaystyle v(tau )=ctanh {frac {gtau }{c}}.} Coordinate time as function of proper time:

{displaystyle t(tau )={frac {c}{g}}sinh {frac {gtau }{c}}.}{displaystyle t(tau )={frac {c}{g}}sinh {frac {gtau }{c}}.} Clock hypothesis The clock hypothesis is the assumption that the rate at which a clock is affected by time dilation does not depend on its acceleration but only on its instantaneous velocity. This is equivalent to stating that a clock moving along a path {displaystyle P}P measures the proper time, defined by:

{displaystyle dtau =int _{P}{sqrt {dt^{2}-dx^{2}/c^{2}-dy^{2}/c^{2}-dz^{2}/c^{2}}}}dtau =int _{P}{sqrt {dt^{2}-dx^{2}/c^{2}-dy^{2}/c^{2}-dz^{2}/c^{2}}}. The clock hypothesis was implicitly (but not explicitly) included in Einstein's original 1905 formulation of special relativity. Since then, it has become a standard assumption and is usually included in the axioms of special relativity, especially in the light of experimental verification up to very high accelerations in particle accelerators.[30][31]

Gravitational time dilation Main article: Gravitational time dilation

Time passes more quickly further from a center of gravity, as is witnessed with massive objects (like the Earth) Gravitational time dilation is experienced by an observer that, at a certain altitude within a gravitational potential well, finds that his local clocks measure less elapsed time than identical clocks situated at higher altitude (and which are therefore at higher gravitational potential).

Gravitational time dilation is at play e.g. for ISS astronauts. While the astronauts' relative velocity slows down their time, the reduced gravitational influence at their location speeds it up, although at a lesser degree. Also, a climber's time is theoretically passing slightly faster at the top of a mountain compared to people at sea level. It has also been calculated that due to time dilation, the core of the Earth is 2.5 years younger than the crust.[32] "A clock used to time a full rotation of the earth will measure the day to be approximately an extra 10 ns/day longer for every km of altitude above the reference geoid."[33] Travel to regions of space where extreme gravitational time dilation is taking place, such as near a black hole, could yield time-shifting results analogous to those of near-lightspeed space travel.

Contrarily to velocity time dilation, in which both observers measure the other as aging slower (a reciprocal effect), gravitational time dilation is not reciprocal. This means that with gravitational time dilation both observers agree that the clock nearer the center of the gravitational field is slower in rate, and they agree on the ratio of the difference.

Experimental testing Main article: Experimental testing of time dilation In 1959 Robert Pound and Glen A. Rebka measured the very slight gravitational redshift in the frequency of light emitted at a lower height, where Earth's gravitational field is relatively more intense. The results were within 10% of the predictions of general relativity. In 1964, Pound and J. L. Snider measured a result within 1% of the value predicted by gravitational time dilation.[34] (See Pound–Rebka experiment) In 2010 gravitational time dilation was measured at the earth's surface with a height difference of only one meter, using optical atomic clocks.[22] Combined effect of velocity and gravitational time dilation

Daily time dilation (gain or loss if negative) in microseconds as a function of (circular) orbit radius r = rs/re, where rs is satellite orbit radius and re is the equatorial Earth radius, calculated using the Schwarzschild metric. At r ? 1.497[Note 1] there is no time dilation. Here the effects of motion and reduced gravity cancel. ISS astronauts fly below, whereas GPS and geostationary satellites fly above.[1]

Daily time dilation over circular orbit height split into its components High-accuracy timekeeping, low-Earth-orbit satellite tracking, and pulsar timing are applications that require the consideration of the combined effects of mass and motion in producing time dilation. Practical examples include the International Atomic Time standard and its relationship with the Barycentric Coordinate Time standard used for interplanetary objects.

Relativistic time dilation effects for the solar system and the earth can be modeled very precisely by the Schwarzschild solution to the Einstein field equations. In the Schwarzschild metric, the interval {displaystyle dt_{text{E}}}{displaystyle dt_{text{E}}} is given by[36][37]

{displaystyle dt_{text{E}}^{2}=left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)dt_{text{c}}^{2}-left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)^{-1}{frac {dx^{2}+dy^{2}+dz^{2}}{c^{2}}},}dt_{text{E}}^{2}=left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)dt_{text{c}}^{2}-left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)^{-1}{frac {dx^{2}+dy^{2}+dz^{2}}{c^{2}}}, where

{displaystyle dt_{text{E}}}{displaystyle dt_{text{E}}} is a small increment of proper time {displaystyle t_{text{E}}}{displaystyle t_{text{E}}} (an interval that could be recorded on an atomic clock), {displaystyle dt_{text{c}}}{displaystyle dt_{text{c}}} is a small increment in the coordinate {displaystyle t_{text{c}}}{displaystyle t_{text{c}}} (coordinate time), {displaystyle dx,dy,dz}{displaystyle dx,dy,dz} are small increments in the three coordinates {displaystyle x,y,z}x, y, z of the clock's position, {displaystyle {frac {GM_{i}}{r_{i}}}}{displaystyle {frac {GM_{i}}{r_{i}}}} represents the sum of the Newtonian gravitational potentials due to the masses in the neighborhood, based on their distances {displaystyle r_{i}}r_{i} from the clock. This sum includes any tidal potentials. The coordinate velocity of the clock is given by

{displaystyle v^{2}={frac {dx^{2}+dy^{2}+dz^{2}}{dt_{text{c}}^{2}}}.,}v^{2}={frac {dx^{2}+dy^{2}+dz^{2}}{dt_{text{c}}^{2}}}., The coordinate time {displaystyle t_{c}}t_c is the time that would be read on a hypothetical "coordinate clock" situated infinitely far from all gravitational masses ({displaystyle U=0}U=0), and stationary in the system of coordinates ({displaystyle v=0}v=0). The exact relation between the rate of proper time and the rate of coordinate time for a clock with a radial component of velocity is

{displaystyle {frac {dt_{text{E}}}{dt_{text{c}}}}={sqrt {1-{frac {2U}{c^{2}}}-{frac {v^{2}}{c^{2}}}-left({frac {c^{2}}{2U}}-1right)^{-1}{frac {{v_{shortparallel }}^{2}}{c^{2}}}}}={sqrt {1-left(beta ^{2}+beta _{e}^{2}+{frac {beta _{shortparallel }^{2}beta _{e}^{2}}{1-beta _{e}^{2}}}right)}},}{displaystyle {frac {dt_{text{E}}}{dt_{text{c}}}}={sqrt {1-{frac {2U}{c^{2}}}-{frac {v^{2}}{c^{2}}}-left({frac {c^{2}}{2U}}-1right)^{-1}{frac {{v_{shortparallel }}^{2}}{c^{2}}}}}={sqrt {1-left(beta ^{2}+beta _{e}^{2}+{frac {beta _{shortparallel }^{2}beta _{e}^{2}}{1-beta _{e}^{2}}}right)}},} where

{displaystyle v_{shortparallel }}{displaystyle v_{shortparallel }} is the radial velocity, {displaystyle v_{e}={sqrt {frac {2GM_{i}}{r_{i}}}}}{displaystyle v_{e}={sqrt {frac {2GM_{i}}{r_{i}}}}} is the escape velocity, {displaystyle beta =v/c}beta = v/c, {displaystyle beta _{e}=v_{e}/c}{displaystyle beta _{e}=v_{e}/c} and {displaystyle beta _{shortparallel }=v_{shortparallel }/c}{displaystyle beta _{shortparallel }=v_{shortparallel }/c} are velocities as a percentage of speed of light c, {displaystyle U={frac {GM_{i}}{r_{i}}}}{displaystyle U={frac {GM_{i}}{r_{i}}}} is the Newtonian potential, equivalent to half of the escape velocity squared. The above equation is exact under the assumptions of the Schwarzschild solution. It reduces to velocity time dilation equation in the presence of motion and absence of gravity, i.e. {displaystyle beta _{e}=0}{displaystyle beta _{e}=0}. It reduces to gravitational time dilation equation in the absence of motion and presence of gravity, i.e. {displaystyle beta =0=beta _{shortparallel }}{displaystyle beta =0=beta _{shortparallel }}.

Experimental testing Hafele and Keating, in 1971, flew caesium atomic clocks east and west around the Earth in commercial airliners, to compare the elapsed time against that of a clock that remained at the U.S. Naval Observatory. Two opposite effects came into play. The clocks were expected to age more quickly (show a larger elapsed time) than the reference clock, since they were in a higher (weaker) gravitational potential for most of the trip (c.f. Pound–Rebka experiment). But also, contrastingly, the moving clocks were expected to age more slowly because of the speed of their travel. From the actual flight paths of each trip, the theory predicted that the flying clocks, compared with reference clocks at the U.S. Naval Observatory, should have lost 40±23 nanoseconds during the eastward trip and should have gained 275±21 nanoseconds during the westward trip. Relative to the atomic time scale of the U.S. Naval Observatory, the flying clocks lost 59±10 nanoseconds during the eastward trip and gained 273±7 nanoseconds during the westward trip (where the error bars represent standard deviation).[38] In 2005, the National Physical Laboratory in the United Kingdom reported their limited replication of this experiment.[39] The NPL experiment differed from the original in that the caesium clocks were sent on a shorter trip (London–Washington, D.C. return), but the clocks were more accurate. The reported results are within 4% of the predictions of relativity, within the uncertainty of the measurements. The Global Positioning System can be considered a continuously operating experiment in both special and general relativity. The in-orbit clocks are corrected for both special and general relativistic time dilation effects as described above, so that (as observed from the earth's surface) they run at the same rate as clocks on the surface of the Earth.[40] icon Physics portal See also Length contraction Mass in special relativity Footnotes Average time dilation has a weak dependence on the orbital inclination angle (Ashby 2003, p.32). The r ? 1.497 result corresponds to[35] the orbital inclination of modern GPS satellites, which is 55 degrees. References Ashby, Neil (2003). "Relativity in the Global Positioning System" (PDF). Living Reviews in Relativity. 6 (1): 16. Bibcode:2003LRR.....6....1A. doi:10.12942/lrr-2003-1. PMC 5253894. PMID 28163638. Lu, Ed. "Expedition 7: Relativity". Ed's Musing from Space. NASA. Retrieved 2018-04-08. "Is time travel possible?". NASA Space Place. Retrieved 2018-08-03. Miller, Arthur I. (1981). Albert Einstein's Special Theory of Relativity: Emergence (1905) and Early Interpretation (1905–1911). Reading, Massachusetts: Addison–Wesley. ISBN 978-0-201-04679-3.. Darrigol, Olivier (2005). The Genesis of the Theory of Relativity (PDF). Séminaire Poincaré. 1. pp. 1–22. doi:10.1007/3-7643-7436-5_1. ISBN 978-3-7643-7435-8. Larmor, Joseph (1897). "On a Dynamical Theory of the Electric and Luminiferous Medium, Part 3, Relations with Material Media" . Philosophical Transactions of the Royal Society. 190: 205–300. Bibcode:1897RSPTA.190..205L. doi:10.1098/rsta.1897.0020. Cohn, Emil (1904), "Zur Elektrodynamik bewegter Systeme II" [On the Electrodynamics of Moving Systems II], Sitzungsberichte der Königlich Preussischen Akademie der Wissenschaften, 1904/2 (43): 1404–1416 Einstein, Albert (1905). "Zur Elektrodynamik bewegter Körper". Annalen der Physik. 322 (10): 891–921. Bibcode:1905AnP...322..891E. doi:10.1002/andp.19053221004.. See also: English translation. Minkowski, Hermann (1908) [1907], "Die Grundgleichungen für die elektromagnetischen Vorgänge in bewegten Körpern" [The Fundamental Equations for Electromagnetic Processes in Moving Bodies], Nachrichten von der Gesellschaft der Wissenschaften zu Göttingen, Mathematisch-Physikalische Klasse: 53–111 Hraskó, Péter (2011). Basic Relativity: An Introductory Essay (illustrated ed.). Springer Science & Business Media. p. 60. ISBN 978-3-642-17810-8. Extract of page 60 Calder, Nigel (2006). Magic Universe: A grand tour of modern science. Oxford University Press. p. 378. ISBN 978-0-19-280669-7. Overbye, Dennis (2005-06-28). "A Trip Forward in Time. Your Travel Agent: Einstein". The New York Times. Retrieved 2015-12-08. Gott, J., Richard (2002). Time Travel in Einstein's Universe. p. 75. Cassidy, David C.; Holton, Gerald James; Rutherford, Floyd James (2002). Understanding Physics. Springer-Verlag. p. 422. ISBN 978-0-387-98756-9. Cutner, Mark Leslie (2003). Astronomy, A Physical Perspective. Cambridge University Press. p. 128. ISBN 978-0-521-82196-4. Lerner, Lawrence S. (1996). Physics for Scientists and Engineers, Volume 2. Jones and Bartlett. pp. 1051–1052. ISBN 978-0-7637-0460-5. Ellis, George F. R.; Williams, Ruth M. (2000). Flat and Curved Space-times (2n ed.). Oxford University Press. pp. 28–29. ISBN 978-0-19-850657-7. Adams, Steve (1997). Relativity: An introduction to space-time physics. CRC Press. p. 54. ISBN 978-0-7484-0621-0. Blaszczak, Z. (2007). Laser 2006. Springer. p. 59. ISBN 978-3540711131. Hasselkamp, D.; Mondry, E.; Scharmann, A. (1979). "Direct observation of the transversal Doppler-shift". Zeitschrift für Physik A. 289 (2): 151–155. Bibcode:1979ZPhyA.289..151H. doi:10.1007/BF01435932. Einstein, A. (1905). "On the electrodynamics of moving bodies". Fourmilab. Chou, C. W.; Hume, D. B.; Rosenband, T.; Wineland, D. J. (2010). "Optical Clocks and Relativity". Science. 329 (5999): 1630–1633. Bibcode:2010Sci...329.1630C. doi:10.1126/science.1192720. PMID 20929843. Stewart, J. V. (2001). Intermediate electromagnetic theory. World Scientific. p. 705. ISBN 978-981-02-4470-5. Bailey, J. et al. Nature 268, 301 (1977) Edwin F. Taylor, John Archibald Wheeler (1992). Spacetime Physics: Introduction to Special Relativity. New York: W. H. Freeman. ISBN 978-0-7167-2327-1. Born, Max (1964), Einstein's Theory of Relativity, Dover Publications, ISBN 978-0-486-60769-6 Petkov, Vesselin (2009). Relativity and the Nature of Spacetime (2nd, illustrated ed.). Springer Science & Business Media. p. 87. ISBN 978-3-642-01962-3. Extract of page 87 See equations 3, 4, 6 and 9 of Iorio, Lorenzo (2005). "An analytical treatment of the Clock Paradox in the framework of the Special and General Theories of Relativity". Foundations of Physics Letters. 18 (1): 1–19. arXiv:physics/0405038. Bibcode:2005FoPhL..18....1I. doi:10.1007/s10702-005-2466-8. Rindler, W. (1977). Essential Relativity. Springer. pp. 49–50. ISBN 978-3540079705. Bailey, H.; Borer, K.; Combley F.; Drumm H.; Krienen F.; Lange F.; Picasso E.; Ruden W. von; Farley F. J. M.; Field J. H.; Flegel W. & Hattersley P. M. (1977). "Measurements of relativistic time dilatation for positive and negative muons in a circular orbit". Nature. 268 (5618): 301–305. Bibcode:1977Natur.268..301B. doi:10.1038/268301a0. Roos, C. E.; Marraffino, J.; Reucroft, S.; Waters, J.; Webster, M. S.; Williams, E. G. H. (1980). "?+/- lifetimes and longitudinal acceleration". Nature. 286 (5770): 244–245. Bibcode:1980Natur.286..244R. doi:10.1038/286244a0. "New calculations show Earth's core is much younger than thought". Phys.org. 26 May 2016. Burns, M. Shane; Leveille, Michael D.; Dominguez, Armand R.; Gebhard, Brian B.; Huestis, Samuel E.; Steele, Jeffrey; Patterson, Brian; Sell, Jerry F.; Serna, Mario; Gearba, M. Alina; Olesen, Robert; O'Shea, Patrick; Schiller, Jonathan (18 September 2017). "Measurement of gravitational time dilation: An undergraduate research project". American Journal of Physics. 85 (10): 757–762. arXiv:1707.00171. doi:10.1119/1.5000802. Pound, R. V.; Snider J. L. (November 2, 1964). "Effect of Gravity on Nuclear Resonance". Physical Review Letters. 13 (18): 539–540. Bibcode:1964PhRvL..13..539P. doi:10.1103/PhysRevLett.13.539. Ashby, Neil (2002). "Relativity in the Global Positioning System". Physics Today. 55 (5): 45. Bibcode:2002PhT....55e..41A. doi:10.1063/1.1485583. See equations 2 & 3 (combined here and divided throughout by c2) at pp. 35–36 in Moyer, T. D. (1981). "Transformation from proper time on Earth to coordinate time in solar system barycentric space-time frame of reference". Celestial Mechanics. 23 (1): 33–56. Bibcode:1981CeMec..23...33M. doi:10.1007/BF01228543. hdl:2060/19770007221. A version of the same relationship can also be seen at equation 2 in Ashbey, Neil (2002). "Relativity and the Global Positioning System" (PDF). Physics Today. 55 (5): 45. Bibcode:2002PhT....55e..41A. doi:10.1063/1.1485583. Nave, C. R. (22 August 2005). "Hafele and Keating Experiment". HyperPhysics. Retrieved 2013-08-05. "Einstein" (PDF). Metromnia. National Physical Laboratory. 2005. pp. 1–4. Kaplan, Elliott; Hegarty, Christopher (2005). Understanding GPS: Principles and Applications. Artech House. p. 306. ISBN 978-1-58053-895-4. Extract of page 306 Further reading Callender, C.; Edney, R. (2001). Introducing Time. Icon Books. ISBN 978-1-84046-592-1. Einstein, A. (1905). "Zur Elektrodynamik bewegter Körper". Annalen der Physik. 322 (10): 891. Bibcode:1905AnP...322..891E. doi:10.1002/andp.19053221004. Einstein, A. (1907). "Über die Möglichkeit einer neuen Prüfung des Relativitätsprinzips". Annalen der Physik. 328 (6): 197–198. Bibcode:1907AnP...328..197E. doi:10.1002/andp.19073280613. Hasselkamp, D.; Mondry, E.; Scharmann, A. (1979). "Direct Observation of the Transversal Doppler-Shift". Zeitschrift für Physik A. 289 (2): 151–155. Bibcode:1979ZPhyA.289..151H. doi:10.1007/BF01435932. Ives, H. E.; Stilwell, G. R. (1938). "An experimental study of the rate of a moving clock". Journal of the Optical Society of America. 28 (7): 215–226. doi:10.1364/JOSA.28.000215. Ives, H. E.; Stilwell, G. R. (1941). "An experimental study of the rate of a moving clock. II". Journal of the Optical Society of America. 31 (5): 369–374. doi:10.1364/JOSA.31.000369. Joos, G. (1959). "Bewegte Bezugssysteme in der Akustik. Der Doppler-Effekt". Lehrbuch der Theoretischen Physik, Zweites Buch (11th ed.). Larmor, J. (1897). "On a dynamical theory of the electric and luminiferous medium". Philosophical Transactions of the Royal Society. 190: 205–300. Bibcode:1897RSPTA.190..205L. doi:10.1098/rsta.1897.0020. (third and last in a series of papers with the same name). Poincaré, H. (1900). "La théorie de Lorentz et le principe de Réaction". Archives Néerlandaises. 5: 253–78. Puri, A. (2015). "Einstein versus the simple pendulum formula: does gravity slow all clocks?". Physics Education. 50 (4): 431. Bibcode:2015PhyEd..50..431P. doi:10.1088/0031-9120/50/4/431. Reinhardt, S.; et al. (2007). "Test of relativistic time dilation with fast optical atomic clocks at different velocities" (PDF). Nature Physics. 3 (12): 861–864. Bibcode:2007NatPh...3..861R. doi:10.1038/nphys778. Archived from the original (PDF) on 2009-07-12. Rossi, B.; Hall, D. B. (1941). "Variation of the Rate of Decay of Mesotrons with Momentum". Physical Review. 59 (3): 223. Bibcode:1941PhRv...59..223R. doi:10.1103/PhysRev.59.223. Weiss, M. "Two way time transfer for satellites". National Institute of Standards and Technology. Archived from the original on 2017-05-29. Voigt, W. (1887). "Über das Doppler'sche princip". Nachrichten von der Königlicher Gesellschaft der Wissenschaften zu Göttingen. 2: 41–51. External links Merrifield, Michael. "Lorentz Factor (and time dilation)". Sixty Symbols. Brady Haran for the University of Nottingham. vte Time vte Time measurement and standards vte Relativity Categories: Special relativityTime in physicsConcepts in physics Navigation menu Not logged inTalkContributionsCreate accountLog inArticleTalkReadEditView historySearch Search Wikipedia Main page Contents Featured content Current events Random article Donate to Wikipedia Wikipedia store Interaction Help About Wikipedia Community portal Recent changes Contact page Tools What links here Related changes Upload file Special pages Permanent link Page information Wikidata item Cite this page In other projects Wikimedia Commons Print/export Download as PDF Printable version

Languages ??????? Español Bahasa Indonesia Bahasa Melayu Português ??????? ?????????? ???? ?? 37 more Edit links This page was last edited on 11 January 2020, at 10:05 (UTC). Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-pro

View Details

Time dilation From Wikipedia, the free encyclopedia Jump to navigationJump to search

Time dilation explains why two working clocks will report different times after different accelerations. For example, at the ISS time goes slower, lagging 0.007 seconds behind for every six months. For GPS satellites to work, they must adjust for similar bending of spacetime to coordinate with systems on Earth.[1] Time dilation is a difference in the elapsed time measured by two clocks, either due to them having a velocity relative to each other, or by there being a gravitational potential difference between their locations. After compensating for varying signal delays due to the changing distance between an observer and a moving clock (i.e. Doppler effect), the observer will measure the moving clock as ticking slower than a clock that is at rest in the observer's own reference frame. A clock that is close to a massive body (and which therefore is at lower gravitational potential) will record less elapsed time than a clock situated further from the said massive body (and which is at a higher gravitational potential).

These predictions of the theory of relativity have been repeatedly confirmed by experiment, and they are of practical concern, for instance in the operation of satellite navigation systems such as GPS and Galileo.[1][2] Time dilation has also been the subject of science fiction works, as it technically provides the means for forward time travel.[3]

Contents 1 History 2 Velocity time dilation 2.1 Simple inference of velocity time dilation 2.2 Reciprocity 2.3 Experimental testing 2.3.1 Doppler effect 2.3.2 Moving particles 2.4 Proper time and Minkowski diagram 2.5 Derivation and formulation 2.6 Hyperbolic motion 2.7 Clock hypothesis 3 Gravitational time dilation 3.1 Experimental testing 4 Combined effect of velocity and gravitational time dilation 4.1 Experimental testing 5 See also 6 Footnotes 7 References 8 Further reading 9 External links History Main article: History of special relativity Time dilation by the Lorentz factor was predicted by several authors at the turn of the 20th century.[4][5] Joseph Larmor (1897), at least for electrons orbiting a nucleus, wrote "... individual electrons describe corresponding parts of their orbits in times shorter for the [rest] system in the ratio :{displaystyle scriptstyle {sqrt {1-{frac {v^{2}}{c^{2}}}}}}scriptstyle {sqrt {1-{frac {v^{2}}{c^{2}}}}}".[6] Emil Cohn (1904) specifically related this formula to the rate of clocks.[7] In the context of special relativity it was shown by Albert Einstein (1905) that this effect concerns the nature of time itself, and he was also the first to point out its reciprocity or symmetry.[8] Subsequently, Hermann Minkowski (1907) introduced the concept of proper time which further clarified the meaning of time dilation.[9]

Velocity time dilation

From the local frame of reference of the blue clock, the red clock, being in motion, is perceived as ticking slower[10] (Exaggerated) Special relativity indicates that, for an observer in an inertial frame of reference, a clock that is moving relative to him will be measured to tick slower than a clock that is at rest in his frame of reference. This case is sometimes called special relativistic time dilation. The faster the relative velocity, the greater the time dilation between one another, with the rate of time reaching zero as one approaches the speed of light (299,792,458 m/s). This causes massless particles that travel at the speed of light to be unaffected by the passage of time.

Theoretically, time dilation would make it possible for passengers in a fast-moving vehicle to advance further into the future in a short period of their own time. For sufficiently high speeds, the effect is dramatic. For example, one year of travel might correspond to ten years on Earth. Indeed, a constant 1 g acceleration would permit humans to travel through the entire known Universe in one human lifetime.[11]

With current technology severely limiting the velocity of space travel, however, the differences experienced in practice are minuscule: after 6 months on the International Space Station (ISS) (which orbits Earth at a speed of about 7,700 m/s[2]) an astronaut would have aged about 0.007 seconds less than those on Earth. The cosmonauts Sergei Krikalev and Sergei Avdeyev both experienced time dilation of about 20 milliseconds compared to time that passed on Earth.[12][13]

Simple inference of velocity time dilation

Left: Observer at rest measures time 2L/c between co-local events of light signal generation at A and arrival at A. Right: Events according to an observer moving to the left of the setup: bottom mirror A when signal is generated at time t'=0, top mirror B when signal gets reflected at time t'=D/c, bottom mirror A when signal returns at time t'=2D/c Time dilation can be inferred from the observed constancy of the speed of light in all reference frames dictated by the second postulate of special relativity.[14][15][16][17]

This constancy of the speed of light means that, counter to intuition, speeds of material objects and light are not additive. It is not possible to make the speed of light appear greater by moving towards or away from the light source.

Consider then, a simple clock consisting of two mirrors A and B, between which a light pulse is bouncing. The separation of the mirrors is L and the clock ticks once each time the light pulse hits either of the mirrors.

In the frame in which the clock is at rest (diagram on the left), the light pulse traces out a path of length 2L and the period of the clock is 2L divided by the speed of light:

{displaystyle Delta t={frac {2L}{c}}.}Delta t={frac {2L}{c}}. From the frame of reference of a moving observer traveling at the speed v relative to the resting frame of the clock (diagram at right), the light pulse is seen as tracing out a longer, angled path. Keeping the speed of light constant for all inertial observers, requires a lengthening of the period of this clock from the moving observer's perspective. That is to say, in a frame moving relative to the local clock, this clock will appear to be running more slowly. Straightforward application of the Pythagorean theorem leads to the well-known prediction of special relativity:

The total time for the light pulse to trace its path is given by

{displaystyle Delta t'={frac {2D}{c}}.}Delta t'={frac {2D}{c}}. The length of the half path can be calculated as a function of known quantities as

{displaystyle D={sqrt {left({frac {1}{2}}vDelta t'right)^{2}+L^{2}}}.}{displaystyle D={sqrt {left({frac {1}{2}}vDelta t'right)^{2}+L^{2}}}.} Elimination of the variables D and L from these three equations results in

{displaystyle Delta t'={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},}{displaystyle Delta t'={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},} which expresses the fact that the moving observer's period of the clock {displaystyle Delta t'}Delta t' is longer than the period {displaystyle Delta t}Delta t in the frame of the clock itself.

Reciprocity

Time UV of a clock in S is shorter compared to Ux? in S?, and time UW of a clock in S? is shorter compared to Ux in S

Transversal time dilation. The blue dots represent a pulse of light. Each pair of dots with light "bouncing" between them is a clock. For each group of clocks, the other group appears to be ticking more slowly, because the moving clock's light pulse has to travel a larger distance than the stationary clock's light pulse. That is so, even though the clocks are identical and their relative motion is perfectly reciprocal. Given a certain frame of reference, and the "stationary" observer described earlier, if a second observer accompanied the "moving" clock, each of the observers would perceive the other's clock as ticking at a slower rate than their own local clock, due to them both perceiving the other to be the one that's in motion relative to their own stationary frame of reference.

Common sense would dictate that, if the passage of time has slowed for a moving object, said object would observe the external world's time to be correspondingly sped up. Counterintuitively, special relativity predicts the opposite. When two observers are in motion relative to each other, each will measure the other's clock slowing down, in concordance with them being moving relative to the observer's frame of reference.

While this seems self-contradictory, a similar oddity occurs in everyday life. If two persons A and B observe each other from a distance, B will appear small to A, but at the same time A will appear small to B. Being familiar with the effects of perspective, there is no contradiction or paradox in this situation.[18]

The reciprocity of the phenomenon also leads to the so-called twin paradox where the aging of twins, one staying on Earth and the other embarking on a space travel, is compared, and where the reciprocity suggests that both persons should have the same age when they reunite. On the contrary, at the end of the round-trip, the traveling twin will be younger than his brother on Earth. The dilemma posed by the paradox, however, can be explained by the fact that the traveling twin must markedly accelerate in at least three phases of the trip (beginning, direction change, and end), while the other will only experience negligible acceleration, due to rotation and revolution of Earth. During the acceleration phases of the space travel, time dilation is not symmetric.

Experimental testing See also: Tests of special relativity Doppler effect Main article: Ives–Stilwell experiment The stated purpose by Ives and Stilwell (1938, 1941) of these experiments was to verify the time dilation effect, predicted by Larmor–Lorentz ether theory, due to motion through the ether using Einstein's suggestion that Doppler effect in canal rays would provide a suitable experiment. These experiments measured the Doppler shift of the radiation emitted from cathode rays, when viewed from directly in front and from directly behind. The high and low frequencies detected were not the classically predicted values {displaystyle {frac {f_{0}}{1-v/c}}qquad {text{and}}qquad {frac {f_{0}}{1+v/c}}.,}{frac {f_{0}}{1-v/c}}qquad {text{and}}qquad {frac {f_{0}}{1+v/c}}., The high and low frequencies of the radiation from the moving sources were measured as[19] {displaystyle {sqrt {frac {1+v/c}{1-v/c}}}f_{0}=gamma left(1+v/cright)f_{0}qquad {text{and}}qquad {sqrt {frac {1-v/c}{1+v/c}}}f_{0}=gamma left(1-v/cright)f_{0},,}{sqrt {frac {1+v/c}{1-v/c}}}f_{0}=gamma left(1+v/cright)f_{0}qquad {text{and}}qquad {sqrt {frac {1-v/c}{1+v/c}}}f_{0}=gamma left(1-v/cright)f_{0},, as deduced by Einstein (1905) from the Lorentz transformation, when the source is running slow by the Lorentz factor. Hasselkamp, Mondry, and Scharmann[20] (1979) measured the Doppler shift from a source moving at right angles to the line of sight. The most general relationship between frequencies of the radiation from the moving sources is given by: {displaystyle f_{mathrm {detected} }=f_{mathrm {rest} }{left(1-{frac {v}{c}}cos phi right)/{sqrt {1-{v^{2}}/{c^{2}}}}}}f_{mathrm {detected} }=f_{mathrm {rest} }{left(1-{frac {v}{c}}cos phi right)/{sqrt {1-{v^{2}}/{c^{2}}}}} as deduced by Einstein (1905).[21] For ? = 90° (cos ? = 0) this reduces to fdetected = frest?. This lower frequency from the moving source can be attributed to the time dilation effect and is often called the transverse Doppler effect and was predicted by relativity. In 2010 time dilation was observed at speeds of less than 10 meters per second using optical atomic clocks connected by 75 meters of optical fiber.[22] Moving particles Main article: Experimental testing of time dilation A comparison of muon lifetimes at different speeds is possible. In the laboratory, slow muons are produced; and in the atmosphere, very fast moving muons are introduced by cosmic rays. Taking the muon lifetime at rest as the laboratory value of 2.197 ?s, the lifetime of a cosmic ray produced muon traveling at 98% of the speed of light is about five times longer, in agreement with observations. An example is Rossi and Hall (1941), who compared the population of cosmic-ray-produced muons at the top of a mountain to that observed at sea level.[23] The lifetime of particles produced in particle accelerators appears longer due to time dilation. In such experiments the "clock" is the time taken by processes leading to muon decay, and these processes take place in the moving muon at its own "clock rate", which is much slower than the laboratory clock. This is routinely taken into account in particle physics, and many dedicated measurements have been performed. For instance, in the muon storage ring at CERN the lifetime of muons circulating with ? = 29.327 was found to be dilated to 64.378 ?s, confirming time dilation to an accuracy of 0.9 ± 0.4 parts per thousand.[24] Proper time and Minkowski diagram Minkowski diagram and twin paradox

Clock C in relative motion between two synchronized clocks A and B. C meets A at d, and B at f.

Twin paradox. One twin has to change frames, leading to different proper times in the twin's world lines. In the Minkowski diagram from the first image on the right, clock C resting in inertial frame S? meets clock A at d and clock B at f (both resting in S). All three clocks simultaneously start to tick in S. The worldline of A is the ct-axis, the worldline of B intersecting f is parallel to the ct-axis, and the worldline of C is the ct?-axis. All events simultaneous with d in S are on the x-axis, in S? on the x?-axis.

The proper time between two events is indicated by a clock present at both events.[25] It is invariant, i.e., in all inertial frames it is agreed that this time is indicated by that clock. Interval df is therefore the proper time of clock C, and is shorter with respect to the coordinate times ef=dg of clocks B and A in S. Conversely, also proper time ef of B is shorter with respect to time if in S?, because event e was measured in S? already at time i due to relativity of simultaneity, long before C started to tick.

From that it can be seen, that the proper time between two events indicated by an unaccelerated clock present at both events, compared with the synchronized coordinate time measured in all other inertial frames, is always the minimal time interval between those events. However, the interval between two events can also correspond to the proper time of accelerated clocks present at both events. Under all possible proper times between two events, the proper time of the unaccelerated clock is maximal, which is the solution to the twin paradox.[25]

Derivation and formulation

Lorentz factor as a function of speed (in natural units where c = 1). Notice that for small speeds (less than 0.1), ? is approximately 1. In addition to the light clock used above, the formula for time dilation can be more generally derived from the temporal part of the Lorentz transformation.[26] Let there be two events at which the moving clock indicates {displaystyle t_{a}}{displaystyle t_{a}} and {displaystyle t_{b}}{displaystyle t_{b}}, thus

{displaystyle t_{a}^{prime }={frac {t_{a}-{frac {vx_{a}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}, t_{b}^{prime }={frac {t_{b}-{frac {vx_{b}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}}{displaystyle t_{a}^{prime }={frac {t_{a}-{frac {vx_{a}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}, t_{b}^{prime }={frac {t_{b}-{frac {vx_{b}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}}. Since the clock remains at rest in its inertial frame, it follows {displaystyle x_{a}=x_{b}}{displaystyle x_{a}=x_{b}}, thus the interval {displaystyle Delta t^{prime }=t_{b}^{prime }-t_{a}^{prime }}{displaystyle Delta t^{prime }=t_{b}^{prime }-t_{a}^{prime }} is given by

{displaystyle Delta t'=gamma ,Delta t={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},}Delta t'=gamma ,Delta t={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}, where ?t is the time interval between two co-local events (i.e. happening at the same place) for an observer in some inertial frame (e.g. ticks on his clock), known as the proper time, ?t? is the time interval between those same events, as measured by another observer, inertially moving with velocity v with respect to the former observer, v is the relative velocity between the observer and the moving clock, c is the speed of light, and the Lorentz factor (conventionally denoted by the Greek letter gamma or ?) is

{displaystyle gamma ={frac {1}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},.}gamma ={frac {1}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},. Thus the duration of the clock cycle of a moving clock is found to be increased: it is measured to be "running slow". The range of such variances in ordinary life, where v ? c, even considering space travel, are not great enough to produce easily detectable time dilation effects and such vanishingly small effects can be safely ignored for most purposes. It is only when an object approaches speeds on the order of 30,000 km/s (1/10 the speed of light) that time dilation becomes important.[27]

Hyperbolic motion Main article: Hyperbolic motion (relativity) In special relativity, time dilation is most simply described in circumstances where relative velocity is unchanging. Nevertheless, the Lorentz equations allow one to calculate proper time and movement in space for the simple case of a spaceship which is applied with a force per unit mass, relative to some reference object in uniform (i.e. constant velocity) motion, equal to g throughout the period of measurement.

Let t be the time in an inertial frame subsequently called the rest frame. Let x be a spatial coordinate, and let the direction of the constant acceleration as well as the spaceship's velocity (relative to the rest frame) be parallel to the x-axis. Assuming the spaceship's position at time t = 0 being x = 0 and the velocity being v0 and defining the following abbreviation

{displaystyle gamma _{0}={frac {1}{sqrt {1-v_{0}^{2}/c^{2}}}},}gamma _{0}={frac {1}{sqrt {1-v_{0}^{2}/c^{2}}}}, the following formulas hold:[28]

Position:

{displaystyle x(t)={frac {c^{2}}{g}}left({sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}-gamma _{0}right).}x(t)={frac {c^{2}}{g}}left({sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}-gamma _{0}right). Velocity:

{displaystyle v(t)={frac {gt+v_{0}gamma _{0}}{sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}}.}v(t)={frac {gt+v_{0}gamma _{0}}{sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}}. Proper time as function of coordinate time:

{displaystyle tau (t)=tau _{0}+int _{0}^{t}{sqrt {1-left({frac {v(t')}{c}}right)^{2}}}dt'.}tau (t)=tau _{0}+int _{0}^{t}{sqrt {1-left({frac {v(t')}{c}}right)^{2}}}dt'. In the case where v(0) = v0 = 0 and ?(0) = ?0 = 0 the integral can be expressed as a logarithmic function or, equivalently, as an inverse hyperbolic function:

{displaystyle tau (t)={frac {c}{g}}ln left({frac {gt}{c}}+{sqrt {1+left({frac {gt}{c}}right)^{2}}}right)={frac {c}{g}}operatorname {arsinh} left({frac {gt}{c}}right).}tau (t)={frac {c}{g}}ln left({frac {gt}{c}}+{sqrt {1+left({frac {gt}{c}}right)^{2}}}right)={frac {c}{g}}operatorname {arsinh} left({frac {gt}{c}}right). As functions of the proper time {displaystyle tau }tau of the ship, the following formulae hold:[29]

Position:

{displaystyle x(tau )={frac {c^{2}}{g}}left(cosh {frac {gtau }{c}}-1right).}{displaystyle x(tau )={frac {c^{2}}{g}}left(cosh {frac {gtau }{c}}-1right).} Velocity:

{displaystyle v(tau )=ctanh {frac {gtau }{c}}.}{displaystyle v(tau )=ctanh {frac {gtau }{c}}.} Coordinate time as function of proper time:

{displaystyle t(tau )={frac {c}{g}}sinh {frac {gtau }{c}}.}{displaystyle t(tau )={frac {c}{g}}sinh {frac {gtau }{c}}.} Clock hypothesis The clock hypothesis is the assumption that the rate at which a clock is affected by time dilation does not depend on its acceleration but only on its instantaneous velocity. This is equivalent to stating that a clock moving along a path {displaystyle P}P measures the proper time, defined by:

{displaystyle dtau =int _{P}{sqrt {dt^{2}-dx^{2}/c^{2}-dy^{2}/c^{2}-dz^{2}/c^{2}}}}dtau =int _{P}{sqrt {dt^{2}-dx^{2}/c^{2}-dy^{2}/c^{2}-dz^{2}/c^{2}}}. The clock hypothesis was implicitly (but not explicitly) included in Einstein's original 1905 formulation of special relativity. Since then, it has become a standard assumption and is usually included in the axioms of special relativity, especially in the light of experimental verification up to very high accelerations in particle accelerators.[30][31]

Gravitational time dilation Main article: Gravitational time dilation

Time passes more quickly further from a center of gravity, as is witnessed with massive objects (like the Earth) Gravitational time dilation is experienced by an observer that, at a certain altitude within a gravitational potential well, finds that his local clocks measure less elapsed time than identical clocks situated at higher altitude (and which are therefore at higher gravitational potential).

Gravitational time dilation is at play e.g. for ISS astronauts. While the astronauts' relative velocity slows down their time, the reduced gravitational influence at their location speeds it up, although at a lesser degree. Also, a climber's time is theoretically passing slightly faster at the top of a mountain compared to people at sea level. It has also been calculated that due to time dilation, the core of the Earth is 2.5 years younger than the crust.[32] "A clock used to time a full rotation of the earth will measure the day to be approximately an extra 10 ns/day longer for every km of altitude above the reference geoid."[33] Travel to regions of space where extreme gravitational time dilation is taking place, such as near a black hole, could yield time-shifting results analogous to those of near-lightspeed space travel.

Contrarily to velocity time dilation, in which both observers measure the other as aging slower (a reciprocal effect), gravitational time dilation is not reciprocal. This means that with gravitational time dilation both observers agree that the clock nearer the center of the gravitational field is slower in rate, and they agree on the ratio of the difference.

Experimental testing Main article: Experimental testing of time dilation In 1959 Robert Pound and Glen A. Rebka measured the very slight gravitational redshift in the frequency of light emitted at a lower height, where Earth's gravitational field is relatively more intense. The results were within 10% of the predictions of general relativity. In 1964, Pound and J. L. Snider measured a result within 1% of the value predicted by gravitational time dilation.[34] (See Pound–Rebka experiment) In 2010 gravitational time dilation was measured at the earth's surface with a height difference of only one meter, using optical atomic clocks.[22] Combined effect of velocity and gravitational time dilation

Daily time dilation (gain or loss if negative) in microseconds as a function of (circular) orbit radius r = rs/re, where rs is satellite orbit radius and re is the equatorial Earth radius, calculated using the Schwarzschild metric. At r ? 1.497[Note 1] there is no time dilation. Here the effects of motion and reduced gravity cancel. ISS astronauts fly below, whereas GPS and geostationary satellites fly above.[1]

Daily time dilation over circular orbit height split into its components High-accuracy timekeeping, low-Earth-orbit satellite tracking, and pulsar timing are applications that require the consideration of the combined effects of mass and motion in producing time dilation. Practical examples include the International Atomic Time standard and its relationship with the Barycentric Coordinate Time standard used for interplanetary objects.

Relativistic time dilation effects for the solar system and the earth can be modeled very precisely by the Schwarzschild solution to the Einstein field equations. In the Schwarzschild metric, the interval {displaystyle dt_{text{E}}}{displaystyle dt_{text{E}}} is given by[36][37]

{displaystyle dt_{text{E}}^{2}=left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)dt_{text{c}}^{2}-left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)^{-1}{frac {dx^{2}+dy^{2}+dz^{2}}{c^{2}}},}dt_{text{E}}^{2}=left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)dt_{text{c}}^{2}-left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)^{-1}{frac {dx^{2}+dy^{2}+dz^{2}}{c^{2}}}, where

{displaystyle dt_{text{E}}}{displaystyle dt_{text{E}}} is a small increment of proper time {displaystyle t_{text{E}}}{displaystyle t_{text{E}}} (an interval that could be recorded on an atomic clock), {displaystyle dt_{text{c}}}{displaystyle dt_{text{c}}} is a small increment in the coordinate {displaystyle t_{text{c}}}{displaystyle t_{text{c}}} (coordinate time), {displaystyle dx,dy,dz}{displaystyle dx,dy,dz} are small increments in the three coordinates {displaystyle x,y,z}x, y, z of the clock's position, {displaystyle {frac {GM_{i}}{r_{i}}}}{displaystyle {frac {GM_{i}}{r_{i}}}} represents the sum of the Newtonian gravitational potentials due to the masses in the neighborhood, based on their distances {displaystyle r_{i}}r_{i} from the clock. This sum includes any tidal potentials. The coordinate velocity of the clock is given by

{displaystyle v^{2}={frac {dx^{2}+dy^{2}+dz^{2}}{dt_{text{c}}^{2}}}.,}v^{2}={frac {dx^{2}+dy^{2}+dz^{2}}{dt_{text{c}}^{2}}}., The coordinate time {displaystyle t_{c}}t_c is the time that would be read on a hypothetical "coordinate clock" situated infinitely far from all gravitational masses ({displaystyle U=0}U=0), and stationary in the system of coordinates ({displaystyle v=0}v=0). The exact relation between the rate of proper time and the rate of coordinate time for a clock with a radial component of velocity is

{displaystyle {frac {dt_{text{E}}}{dt_{text{c}}}}={sqrt {1-{frac {2U}{c^{2}}}-{frac {v^{2}}{c^{2}}}-left({frac {c^{2}}{2U}}-1right)^{-1}{frac {{v_{shortparallel }}^{2}}{c^{2}}}}}={sqrt {1-left(beta ^{2}+beta _{e}^{2}+{frac {beta _{shortparallel }^{2}beta _{e}^{2}}{1-beta _{e}^{2}}}right)}},}{displaystyle {frac {dt_{text{E}}}{dt_{text{c}}}}={sqrt {1-{frac {2U}{c^{2}}}-{frac {v^{2}}{c^{2}}}-left({frac {c^{2}}{2U}}-1right)^{-1}{frac {{v_{shortparallel }}^{2}}{c^{2}}}}}={sqrt {1-left(beta ^{2}+beta _{e}^{2}+{frac {beta _{shortparallel }^{2}beta _{e}^{2}}{1-beta _{e}^{2}}}right)}},} where

{displaystyle v_{shortparallel }}{displaystyle v_{shortparallel }} is the radial velocity, {displaystyle v_{e}={sqrt {frac {2GM_{i}}{r_{i}}}}}{displaystyle v_{e}={sqrt {frac {2GM_{i}}{r_{i}}}}} is the escape velocity, {displaystyle beta =v/c}beta = v/c, {displaystyle beta _{e}=v_{e}/c}{displaystyle beta _{e}=v_{e}/c} and {displaystyle beta _{shortparallel }=v_{shortparallel }/c}{displaystyle beta _{shortparallel }=v_{shortparallel }/c} are velocities as a percentage of speed of light c, {displaystyle U={frac {GM_{i}}{r_{i}}}}{displaystyle U={frac {GM_{i}}{r_{i}}}} is the Newtonian potential, equivalent to half of the escape velocity squared. The above equation is exact under the assumptions of the Schwarzschild solution. It reduces to velocity time dilation equation in the presence of motion and absence of gravity, i.e. {displaystyle beta _{e}=0}{displaystyle beta _{e}=0}. It reduces to gravitational time dilation equation in the absence of motion and presence of gravity, i.e. {displaystyle beta =0=beta _{shortparallel }}{displaystyle beta =0=beta _{shortparallel }}.

Experimental testing Hafele and Keating, in 1971, flew caesium atomic clocks east and west around the Earth in commercial airliners, to compare the elapsed time against that of a clock that remained at the U.S. Naval Observatory. Two opposite effects came into play. The clocks were expected to age more quickly (show a larger elapsed time) than the reference clock, since they were in a higher (weaker) gravitational potential for most of the trip (c.f. Pound–Rebka experiment). But also, contrastingly, the moving clocks were expected to age more slowly because of the speed of their travel. From the actual flight paths of each trip, the theory predicted that the flying clocks, compared with reference clocks at the U.S. Naval Observatory, should have lost 40±23 nanoseconds during the eastward trip and should have gained 275±21 nanoseconds during the westward trip. Relative to the atomic time scale of the U.S. Naval Observatory, the flying clocks lost 59±10 nanoseconds during the eastward trip and gained 273±7 nanoseconds during the westward trip (where the error bars represent standard deviation).[38] In 2005, the National Physical Laboratory in the United Kingdom reported their limited replication of this experiment.[39] The NPL experiment differed from the original in that the caesium clocks were sent on a shorter trip (London–Washington, D.C. return), but the clocks were more accurate. The reported results are within 4% of the predictions of relativity, within the uncertainty of the measurements. The Global Positioning System can be considered a continuously operating experiment in both special and general relativity. The in-orbit clocks are corrected for both special and general relativistic time dilation effects as described above, so that (as observed from the earth's surface) they run at the same rate as clocks on the surface of the Earth.[40] icon Physics portal See also Length contraction Mass in special relativity Footnotes Average time dilation has a weak dependence on the orbital inclination angle (Ashby 2003, p.32). The r ? 1.497 result corresponds to[35] the orbital inclination of modern GPS satellites, which is 55 degrees. References Ashby, Neil (2003). "Relativity in the Global Positioning System" (PDF). Living Reviews in Relativity. 6 (1): 16. Bibcode:2003LRR.....6....1A. doi:10.12942/lrr-2003-1. PMC 5253894. PMID 28163638. Lu, Ed. "Expedition 7: Relativity". Ed's Musing from Space. NASA. Retrieved 2018-04-08. "Is time travel possible?". NASA Space Place. Retrieved 2018-08-03. Miller, Arthur I. (1981). Albert Einstein's Special Theory of Relativity: Emergence (1905) and Early Interpretation (1905–1911). Reading, Massachusetts: Addison–Wesley. ISBN 978-0-201-04679-3.. Darrigol, Olivier (2005). The Genesis of the Theory of Relativity (PDF). Séminaire Poincaré. 1. pp. 1–22. doi:10.1007/3-7643-7436-5_1. ISBN 978-3-7643-7435-8. Larmor, Joseph (1897). "On a Dynamical Theory of the Electric and Luminiferous Medium, Part 3, Relations with Material Media" . Philosophical Transactions of the Royal Society. 190: 205–300. Bibcode:1897RSPTA.190..205L. doi:10.1098/rsta.1897.0020. Cohn, Emil (1904), "Zur Elektrodynamik bewegter Systeme II" [On the Electrodynamics of Moving Systems II], Sitzungsberichte der Königlich Preussischen Akademie der Wissenschaften, 1904/2 (43): 1404–1416 Einstein, Albert (1905). "Zur Elektrodynamik bewegter Körper". Annalen der Physik. 322 (10): 891–921. Bibcode:1905AnP...322..891E. doi:10.1002/andp.19053221004.. See also: English translation. Minkowski, Hermann (1908) [1907], "Die Grundgleichungen für die elektromagnetischen Vorgänge in bewegten Körpern" [The Fundamental Equations for Electromagnetic Processes in Moving Bodies], Nachrichten von der Gesellschaft der Wissenschaften zu Göttingen, Mathematisch-Physikalische Klasse: 53–111 Hraskó, Péter (2011). Basic Relativity: An Introductory Essay (illustrated ed.). Springer Science & Business Media. p. 60. ISBN 978-3-642-17810-8. Extract of page 60 Calder, Nigel (2006). Magic Universe: A grand tour of modern science. Oxford University Press. p. 378. ISBN 978-0-19-280669-7. Overbye, Dennis (2005-06-28). "A Trip Forward in Time. Your Travel Agent: Einstein". The New York Times. Retrieved 2015-12-08. Gott, J., Richard (2002). Time Travel in Einstein's Universe. p. 75. Cassidy, David C.; Holton, Gerald James; Rutherford, Floyd James (2002). Understanding Physics. Springer-Verlag. p. 422. ISBN 978-0-387-98756-9. Cutner, Mark Leslie (2003). Astronomy, A Physical Perspective. Cambridge University Press. p. 128. ISBN 978-0-521-82196-4. Lerner, Lawrence S. (1996). Physics for Scientists and Engineers, Volume 2. Jones and Bartlett. pp. 1051–1052. ISBN 978-0-7637-0460-5. Ellis, George F. R.; Williams, Ruth M. (2000). Flat and Curved Space-times (2n ed.). Oxford University Press. pp. 28–29. ISBN 978-0-19-850657-7. Adams, Steve (1997). Relativity: An introduction to space-time physics. CRC Press. p. 54. ISBN 978-0-7484-0621-0. Blaszczak, Z. (2007). Laser 2006. Springer. p. 59. ISBN 978-3540711131. Hasselkamp, D.; Mondry, E.; Scharmann, A. (1979). "Direct observation of the transversal Doppler-shift". Zeitschrift für Physik A. 289 (2): 151–155. Bibcode:1979ZPhyA.289..151H. doi:10.1007/BF01435932. Einstein, A. (1905). "On the electrodynamics of moving bodies". Fourmilab. Chou, C. W.; Hume, D. B.; Rosenband, T.; Wineland, D. J. (2010). "Optical Clocks and Relativity". Science. 329 (5999): 1630–1633. Bibcode:2010Sci...329.1630C. doi:10.1126/science.1192720. PMID 20929843. Stewart, J. V. (2001). Intermediate electromagnetic theory. World Scientific. p. 705. ISBN 978-981-02-4470-5. Bailey, J. et al. Nature 268, 301 (1977) Edwin F. Taylor, John Archibald Wheeler (1992). Spacetime Physics: Introduction to Special Relativity. New York: W. H. Freeman. ISBN 978-0-7167-2327-1. Born, Max (1964), Einstein's Theory of Relativity, Dover Publications, ISBN 978-0-486-60769-6 Petkov, Vesselin (2009). Relativity and the Nature of Spacetime (2nd, illustrated ed.). Springer Science & Business Media. p. 87. ISBN 978-3-642-01962-3. Extract of page 87 See equations 3, 4, 6 and 9 of Iorio, Lorenzo (2005). "An analytical treatment of the Clock Paradox in the framework of the Special and General Theories of Relativity". Foundations of Physics Letters. 18 (1): 1–19. arXiv:physics/0405038. Bibcode:2005FoPhL..18....1I. doi:10.1007/s10702-005-2466-8. Rindler, W. (1977). Essential Relativity. Springer. pp. 49–50. ISBN 978-3540079705. Bailey, H.; Borer, K.; Combley F.; Drumm H.; Krienen F.; Lange F.; Picasso E.; Ruden W. von; Farley F. J. M.; Field J. H.; Flegel W. & Hattersley P. M. (1977). "Measurements of relativistic time dilatation for positive and negative muons in a circular orbit". Nature. 268 (5618): 301–305. Bibcode:1977Natur.268..301B. doi:10.1038/268301a0. Roos, C. E.; Marraffino, J.; Reucroft, S.; Waters, J.; Webster, M. S.; Williams, E. G. H. (1980). "?+/- lifetimes and longitudinal acceleration". Nature. 286 (5770): 244–245. Bibcode:1980Natur.286..244R. doi:10.1038/286244a0. "New calculations show Earth's core is much younger than thought". Phys.org. 26 May 2016. Burns, M. Shane; Leveille, Michael D.; Dominguez, Armand R.; Gebhard, Brian B.; Huestis, Samuel E.; Steele, Jeffrey; Patterson, Brian; Sell, Jerry F.; Serna, Mario; Gearba, M. Alina; Olesen, Robert; O'Shea, Patrick; Schiller, Jonathan (18 September 2017). "Measurement of gravitational time dilation: An undergraduate research project". American Journal of Physics. 85 (10): 757–762. arXiv:1707.00171. doi:10.1119/1.5000802. Pound, R. V.; Snider J. L. (November 2, 1964). "Effect of Gravity on Nuclear Resonance". Physical Review Letters. 13 (18): 539–540. Bibcode:1964PhRvL..13..539P. doi:10.1103/PhysRevLett.13.539. Ashby, Neil (2002). "Relativity in the Global Positioning System". Physics Today. 55 (5): 45. Bibcode:2002PhT....55e..41A. doi:10.1063/1.1485583. See equations 2 & 3 (combined here and divided throughout by c2) at pp. 35–36 in Moyer, T. D. (1981). "Transformation from proper time on Earth to coordinate time in solar system barycentric space-time frame of reference". Celestial Mechanics. 23 (1): 33–56. Bibcode:1981CeMec..23...33M. doi:10.1007/BF01228543. hdl:2060/19770007221. A version of the same relationship can also be seen at equation 2 in Ashbey, Neil (2002). "Relativity and the Global Positioning System" (PDF). Physics Today. 55 (5): 45. Bibcode:2002PhT....55e..41A. doi:10.1063/1.1485583. Nave, C. R. (22 August 2005). "Hafele and Keating Experiment". HyperPhysics. Retrieved 2013-08-05. "Einstein" (PDF). Metromnia. National Physical Laboratory. 2005. pp. 1–4. Kaplan, Elliott; Hegarty, Christopher (2005). Understanding GPS: Principles and Applications. Artech House. p. 306. ISBN 978-1-58053-895-4. Extract of page 306 Further reading Callender, C.; Edney, R. (2001). Introducing Time. Icon Books. ISBN 978-1-84046-592-1. Einstein, A. (1905). "Zur Elektrodynamik bewegter Körper". Annalen der Physik. 322 (10): 891. Bibcode:1905AnP...322..891E. doi:10.1002/andp.19053221004. Einstein, A. (1907). "Über die Möglichkeit einer neuen Prüfung des Relativitätsprinzips". Annalen der Physik. 328 (6): 197–198. Bibcode:1907AnP...328..197E. doi:10.1002/andp.19073280613. Hasselkamp, D.; Mondry, E.; Scharmann, A. (1979). "Direct Observation of the Transversal Doppler-Shift". Zeitschrift für Physik A. 289 (2): 151–155. Bibcode:1979ZPhyA.289..151H. doi:10.1007/BF01435932. Ives, H. E.; Stilwell, G. R. (1938). "An experimental study of the rate of a moving clock". Journal of the Optical Society of America. 28 (7): 215–226. doi:10.1364/JOSA.28.000215. Ives, H. E.; Stilwell, G. R. (1941). "An experimental study of the rate of a moving clock. II". Journal of the Optical Society of America. 31 (5): 369–374. doi:10.1364/JOSA.31.000369. Joos, G. (1959). "Bewegte Bezugssysteme in der Akustik. Der Doppler-Effekt". Lehrbuch der Theoretischen Physik, Zweites Buch (11th ed.). Larmor, J. (1897). "On a dynamical theory of the electric and luminiferous medium". Philosophical Transactions of the Royal Society. 190: 205–300. Bibcode:1897RSPTA.190..205L. doi:10.1098/rsta.1897.0020. (third and last in a series of papers with the same name). Poincaré, H. (1900). "La théorie de Lorentz et le principe de Réaction". Archives Néerlandaises. 5: 253–78. Puri, A. (2015). "Einstein versus the simple pendulum formula: does gravity slow all clocks?". Physics Education. 50 (4): 431. Bibcode:2015PhyEd..50..431P. doi:10.1088/0031-9120/50/4/431. Reinhardt, S.; et al. (2007). "Test of relativistic time dilation with fast optical atomic clocks at different velocities" (PDF). Nature Physics. 3 (12): 861–864. Bibcode:2007NatPh...3..861R. doi:10.1038/nphys778. Archived from the original (PDF) on 2009-07-12. Rossi, B.; Hall, D. B. (1941). "Variation of the Rate of Decay of Mesotrons with Momentum". Physical Review. 59 (3): 223. Bibcode:1941PhRv...59..223R. doi:10.1103/PhysRev.59.223. Weiss, M. "Two way time transfer for satellites". National Institute of Standards and Technology. Archived from the original on 2017-05-29. Voigt, W. (1887). "Über das Doppler'sche princip". Nachrichten von der Königlicher Gesellschaft der Wissenschaften zu Göttingen. 2: 41–51. External links Merrifield, Michael. "Lorentz Factor (and time dilation)". Sixty Symbols. Brady Haran for the University of Nottingham. vte Time vte Time measurement and standards vte Relativity Categories: Special relativityTime in physicsConcepts in physics Navigation menu Not logged inTalkContributionsCreate accountLog inArticleTalkReadEditView historySearch Search Wikipedia Main page Contents Featured content Current events Random article Donate to Wikipedia Wikipedia store Interaction Help About Wikipedia Community portal Recent changes Contact page Tools What links here Related changes Upload file Special pages Permanent link Page information Wikidata item Cite this page In other projects Wikimedia Commons Print/export Download as PDF Printable version

Languages ??????? Español Bahasa Indonesia Bahasa Melayu Português ??????? ?????????? ???? ?? 37 more Edit links This page was last edited on 11 January 2020, at 10:05 (UTC). Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-pro

View Details

Sartre in 90 MinutesTime dilation From Wikipedia, the free encyclopedia Jump to navigationJump to search

Time dilation explains why two working clocks will report different times after different accelerations. For example, at the ISS time goes slower, lagging 0.007 seconds behind for every six months. For GPS satellites to work, they must adjust for similar bending of spacetime to coordinate with systems on Earth.[1] Time dilation is a difference in the elapsed time measured by two clocks, either due to them having a velocity relative to each other, or by there being a gravitational potential difference between their locations. After compensating for varying signal delays due to the changing distance between an observer and a moving clock (i.e. Doppler effect), the observer will measure the moving clock as ticking slower than a clock that is at rest in the observer's own reference frame. A clock that is close to a massive body (and which therefore is at lower gravitational potential) will record less elapsed time than a clock situated further from the said massive body (and which is at a higher gravitational potential).

These predictions of the theory of relativity have been repeatedly confirmed by experiment, and they are of practical concern, for instance in the operation of satellite navigation systems such as GPS and Galileo.[1][2] Time dilation has also been the subject of science fiction works, as it technically provides the means for forward time travel.[3]

Contents 1 History 2 Velocity time dilation 2.1 Simple inference of velocity time dilation 2.2 Reciprocity 2.3 Experimental testing 2.3.1 Doppler effect 2.3.2 Moving particles 2.4 Proper time and Minkowski diagram 2.5 Derivation and formulation 2.6 Hyperbolic motion 2.7 Clock hypothesis 3 Gravitational time dilation 3.1 Experimental testing 4 Combined effect of velocity and gravitational time dilation 4.1 Experimental testing 5 See also 6 Footnotes 7 References 8 Further reading 9 External links History Main article: History of special relativity Time dilation by the Lorentz factor was predicted by several authors at the turn of the 20th century.[4][5] Joseph Larmor (1897), at least for electrons orbiting a nucleus, wrote "... individual electrons describe corresponding parts of their orbits in times shorter for the [rest] system in the ratio :{displaystyle scriptstyle {sqrt {1-{frac {v^{2}}{c^{2}}}}}}scriptstyle {sqrt {1-{frac {v^{2}}{c^{2}}}}}".[6] Emil Cohn (1904) specifically related this formula to the rate of clocks.[7] In the context of special relativity it was shown by Albert Einstein (1905) that this effect concerns the nature of time itself, and he was also the first to point out its reciprocity or symmetry.[8] Subsequently, Hermann Minkowski (1907) introduced the concept of proper time which further clarified the meaning of time dilation.[9]

Velocity time dilation

From the local frame of reference of the blue clock, the red clock, being in motion, is perceived as ticking slower[10] (Exaggerated) Special relativity indicates that, for an observer in an inertial frame of reference, a clock that is moving relative to him will be measured to tick slower than a clock that is at rest in his frame of reference. This case is sometimes called special relativistic time dilation. The faster the relative velocity, the greater the time dilation between one another, with the rate of time reaching zero as one approaches the speed of light (299,792,458 m/s). This causes massless particles that travel at the speed of light to be unaffected by the passage of time.

Theoretically, time dilation would make it possible for passengers in a fast-moving vehicle to advance further into the future in a short period of their own time. For sufficiently high speeds, the effect is dramatic. For example, one year of travel might correspond to ten years on Earth. Indeed, a constant 1 g acceleration would permit humans to travel through the entire known Universe in one human lifetime.[11]

With current technology severely limiting the velocity of space travel, however, the differences experienced in practice are minuscule: after 6 months on the International Space Station (ISS) (which orbits Earth at a speed of about 7,700 m/s[2]) an astronaut would have aged about 0.007 seconds less than those on Earth. The cosmonauts Sergei Krikalev and Sergei Avdeyev both experienced time dilation of about 20 milliseconds compared to time that passed on Earth.[12][13]

Simple inference of velocity time dilation

Left: Observer at rest measures time 2L/c between co-local events of light signal generation at A and arrival at A. Right: Events according to an observer moving to the left of the setup: bottom mirror A when signal is generated at time t'=0, top mirror B when signal gets reflected at time t'=D/c, bottom mirror A when signal returns at time t'=2D/c Time dilation can be inferred from the observed constancy of the speed of light in all reference frames dictated by the second postulate of special relativity.[14][15][16][17]

This constancy of the speed of light means that, counter to intuition, speeds of material objects and light are not additive. It is not possible to make the speed of light appear greater by moving towards or away from the light source.

Consider then, a simple clock consisting of two mirrors A and B, between which a light pulse is bouncing. The separation of the mirrors is L and the clock ticks once each time the light pulse hits either of the mirrors.

In the frame in which the clock is at rest (diagram on the left), the light pulse traces out a path of length 2L and the period of the clock is 2L divided by the speed of light:

{displaystyle Delta t={frac {2L}{c}}.}Delta t={frac {2L}{c}}. From the frame of reference of a moving observer traveling at the speed v relative to the resting frame of the clock (diagram at right), the light pulse is seen as tracing out a longer, angled path. Keeping the speed of light constant for all inertial observers, requires a lengthening of the period of this clock from the moving observer's perspective. That is to say, in a frame moving relative to the local clock, this clock will appear to be running more slowly. Straightforward application of the Pythagorean theorem leads to the well-known prediction of special relativity:

The total time for the light pulse to trace its path is given by

{displaystyle Delta t'={frac {2D}{c}}.}Delta t'={frac {2D}{c}}. The length of the half path can be calculated as a function of known quantities as

{displaystyle D={sqrt {left({frac {1}{2}}vDelta t'right)^{2}+L^{2}}}.}{displaystyle D={sqrt {left({frac {1}{2}}vDelta t'right)^{2}+L^{2}}}.} Elimination of the variables D and L from these three equations results in

{displaystyle Delta t'={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},}{displaystyle Delta t'={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},} which expresses the fact that the moving observer's period of the clock {displaystyle Delta t'}Delta t' is longer than the period {displaystyle Delta t}Delta t in the frame of the clock itself.

Reciprocity

Time UV of a clock in S is shorter compared to Ux? in S?, and time UW of a clock in S? is shorter compared to Ux in S

Transversal time dilation. The blue dots represent a pulse of light. Each pair of dots with light "bouncing" between them is a clock. For each group of clocks, the other group appears to be ticking more slowly, because the moving clock's light pulse has to travel a larger distance than the stationary clock's light pulse. That is so, even though the clocks are identical and their relative motion is perfectly reciprocal. Given a certain frame of reference, and the "stationary" observer described earlier, if a second observer accompanied the "moving" clock, each of the observers would perceive the other's clock as ticking at a slower rate than their own local clock, due to them both perceiving the other to be the one that's in motion relative to their own stationary frame of reference.

Common sense would dictate that, if the passage of time has slowed for a moving object, said object would observe the external world's time to be correspondingly sped up. Counterintuitively, special relativity predicts the opposite. When two observers are in motion relative to each other, each will measure the other's clock slowing down, in concordance with them being moving relative to the observer's frame of reference.

While this seems self-contradictory, a similar oddity occurs in everyday life. If two persons A and B observe each other from a distance, B will appear small to A, but at the same time A will appear small to B. Being familiar with the effects of perspective, there is no contradiction or paradox in this situation.[18]

The reciprocity of the phenomenon also leads to the so-called twin paradox where the aging of twins, one staying on Earth and the other embarking on a space travel, is compared, and where the reciprocity suggests that both persons should have the same age when they reunite. On the contrary, at the end of the round-trip, the traveling twin will be younger than his brother on Earth. The dilemma posed by the paradox, however, can be explained by the fact that the traveling twin must markedly accelerate in at least three phases of the trip (beginning, direction change, and end), while the other will only experience negligible acceleration, due to rotation and revolution of Earth. During the acceleration phases of the space travel, time dilation is not symmetric.

Experimental testing See also: Tests of special relativity Doppler effect Main article: Ives–Stilwell experiment The stated purpose by Ives and Stilwell (1938, 1941) of these experiments was to verify the time dilation effect, predicted by Larmor–Lorentz ether theory, due to motion through the ether using Einstein's suggestion that Doppler effect in canal rays would provide a suitable experiment. These experiments measured the Doppler shift of the radiation emitted from cathode rays, when viewed from directly in front and from directly behind. The high and low frequencies detected were not the classically predicted values {displaystyle {frac {f_{0}}{1-v/c}}qquad {text{and}}qquad {frac {f_{0}}{1+v/c}}.,}{frac {f_{0}}{1-v/c}}qquad {text{and}}qquad {frac {f_{0}}{1+v/c}}., The high and low frequencies of the radiation from the moving sources were measured as[19] {displaystyle {sqrt {frac {1+v/c}{1-v/c}}}f_{0}=gamma left(1+v/cright)f_{0}qquad {text{and}}qquad {sqrt {frac {1-v/c}{1+v/c}}}f_{0}=gamma left(1-v/cright)f_{0},,}{sqrt {frac {1+v/c}{1-v/c}}}f_{0}=gamma left(1+v/cright)f_{0}qquad {text{and}}qquad {sqrt {frac {1-v/c}{1+v/c}}}f_{0}=gamma left(1-v/cright)f_{0},, as deduced by Einstein (1905) from the Lorentz transformation, when the source is running slow by the Lorentz factor. Hasselkamp, Mondry, and Scharmann[20] (1979) measured the Doppler shift from a source moving at right angles to the line of sight. The most general relationship between frequencies of the radiation from the moving sources is given by: {displaystyle f_{mathrm {detected} }=f_{mathrm {rest} }{left(1-{frac {v}{c}}cos phi right)/{sqrt {1-{v^{2}}/{c^{2}}}}}}f_{mathrm {detected} }=f_{mathrm {rest} }{left(1-{frac {v}{c}}cos phi right)/{sqrt {1-{v^{2}}/{c^{2}}}}} as deduced by Einstein (1905).[21] For ? = 90° (cos ? = 0) this reduces to fdetected = frest?. This lower frequency from the moving source can be attributed to the time dilation effect and is often called the transverse Doppler effect and was predicted by relativity. In 2010 time dilation was observed at speeds of less than 10 meters per second using optical atomic clocks connected by 75 meters of optical fiber.[22] Moving particles Main article: Experimental testing of time dilation A comparison of muon lifetimes at different speeds is possible. In the laboratory, slow muons are produced; and in the atmosphere, very fast moving muons are introduced by cosmic rays. Taking the muon lifetime at rest as the laboratory value of 2.197 ?s, the lifetime of a cosmic ray produced muon traveling at 98% of the speed of light is about five times longer, in agreement with observations. An example is Rossi and Hall (1941), who compared the population of cosmic-ray-produced muons at the top of a mountain to that observed at sea level.[23] The lifetime of particles produced in particle accelerators appears longer due to time dilation. In such experiments the "clock" is the time taken by processes leading to muon decay, and these processes take place in the moving muon at its own "clock rate", which is much slower than the laboratory clock. This is routinely taken into account in particle physics, and many dedicated measurements have been performed. For instance, in the muon storage ring at CERN the lifetime of muons circulating with ? = 29.327 was found to be dilated to 64.378 ?s, confirming time dilation to an accuracy of 0.9 ± 0.4 parts per thousand.[24] Proper time and Minkowski diagram Minkowski diagram and twin paradox

Clock C in relative motion between two synchronized clocks A and B. C meets A at d, and B at f.

Twin paradox. One twin has to change frames, leading to different proper times in the twin's world lines. In the Minkowski diagram from the first image on the right, clock C resting in inertial frame S? meets clock A at d and clock B at f (both resting in S). All three clocks simultaneously start to tick in S. The worldline of A is the ct-axis, the worldline of B intersecting f is parallel to the ct-axis, and the worldline of C is the ct?-axis. All events simultaneous with d in S are on the x-axis, in S? on the x?-axis.

The proper time between two events is indicated by a clock present at both events.[25] It is invariant, i.e., in all inertial frames it is agreed that this time is indicated by that clock. Interval df is therefore the proper time of clock C, and is shorter with respect to the coordinate times ef=dg of clocks B and A in S. Conversely, also proper time ef of B is shorter with respect to time if in S?, because event e was measured in S? already at time i due to relativity of simultaneity, long before C started to tick.

From that it can be seen, that the proper time between two events indicated by an unaccelerated clock present at both events, compared with the synchronized coordinate time measured in all other inertial frames, is always the minimal time interval between those events. However, the interval between two events can also correspond to the proper time of accelerated clocks present at both events. Under all possible proper times between two events, the proper time of the unaccelerated clock is maximal, which is the solution to the twin paradox.[25]

Derivation and formulation

Lorentz factor as a function of speed (in natural units where c = 1). Notice that for small speeds (less than 0.1), ? is approximately 1. In addition to the light clock used above, the formula for time dilation can be more generally derived from the temporal part of the Lorentz transformation.[26] Let there be two events at which the moving clock indicates {displaystyle t_{a}}{displaystyle t_{a}} and {displaystyle t_{b}}{displaystyle t_{b}}, thus

{displaystyle t_{a}^{prime }={frac {t_{a}-{frac {vx_{a}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}, t_{b}^{prime }={frac {t_{b}-{frac {vx_{b}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}}{displaystyle t_{a}^{prime }={frac {t_{a}-{frac {vx_{a}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}, t_{b}^{prime }={frac {t_{b}-{frac {vx_{b}}{c^{2}}}}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}}. Since the clock remains at rest in its inertial frame, it follows {displaystyle x_{a}=x_{b}}{displaystyle x_{a}=x_{b}}, thus the interval {displaystyle Delta t^{prime }=t_{b}^{prime }-t_{a}^{prime }}{displaystyle Delta t^{prime }=t_{b}^{prime }-t_{a}^{prime }} is given by

{displaystyle Delta t'=gamma ,Delta t={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},}Delta t'=gamma ,Delta t={frac {Delta t}{sqrt {1-{frac {v^{2}}{c^{2}}}}}}, where ?t is the time interval between two co-local events (i.e. happening at the same place) for an observer in some inertial frame (e.g. ticks on his clock), known as the proper time, ?t? is the time interval between those same events, as measured by another observer, inertially moving with velocity v with respect to the former observer, v is the relative velocity between the observer and the moving clock, c is the speed of light, and the Lorentz factor (conventionally denoted by the Greek letter gamma or ?) is

{displaystyle gamma ={frac {1}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},.}gamma ={frac {1}{sqrt {1-{frac {v^{2}}{c^{2}}}}}},. Thus the duration of the clock cycle of a moving clock is found to be increased: it is measured to be "running slow". The range of such variances in ordinary life, where v ? c, even considering space travel, are not great enough to produce easily detectable time dilation effects and such vanishingly small effects can be safely ignored for most purposes. It is only when an object approaches speeds on the order of 30,000 km/s (1/10 the speed of light) that time dilation becomes important.[27]

Hyperbolic motion Main article: Hyperbolic motion (relativity) In special relativity, time dilation is most simply described in circumstances where relative velocity is unchanging. Nevertheless, the Lorentz equations allow one to calculate proper time and movement in space for the simple case of a spaceship which is applied with a force per unit mass, relative to some reference object in uniform (i.e. constant velocity) motion, equal to g throughout the period of measurement.

Let t be the time in an inertial frame subsequently called the rest frame. Let x be a spatial coordinate, and let the direction of the constant acceleration as well as the spaceship's velocity (relative to the rest frame) be parallel to the x-axis. Assuming the spaceship's position at time t = 0 being x = 0 and the velocity being v0 and defining the following abbreviation

{displaystyle gamma _{0}={frac {1}{sqrt {1-v_{0}^{2}/c^{2}}}},}gamma _{0}={frac {1}{sqrt {1-v_{0}^{2}/c^{2}}}}, the following formulas hold:[28]

Position:

{displaystyle x(t)={frac {c^{2}}{g}}left({sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}-gamma _{0}right).}x(t)={frac {c^{2}}{g}}left({sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}-gamma _{0}right). Velocity:

{displaystyle v(t)={frac {gt+v_{0}gamma _{0}}{sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}}.}v(t)={frac {gt+v_{0}gamma _{0}}{sqrt {1+{frac {left(gt+v_{0}gamma _{0}right)^{2}}{c^{2}}}}}}. Proper time as function of coordinate time:

{displaystyle tau (t)=tau _{0}+int _{0}^{t}{sqrt {1-left({frac {v(t')}{c}}right)^{2}}}dt'.}tau (t)=tau _{0}+int _{0}^{t}{sqrt {1-left({frac {v(t')}{c}}right)^{2}}}dt'. In the case where v(0) = v0 = 0 and ?(0) = ?0 = 0 the integral can be expressed as a logarithmic function or, equivalently, as an inverse hyperbolic function:

{displaystyle tau (t)={frac {c}{g}}ln left({frac {gt}{c}}+{sqrt {1+left({frac {gt}{c}}right)^{2}}}right)={frac {c}{g}}operatorname {arsinh} left({frac {gt}{c}}right).}tau (t)={frac {c}{g}}ln left({frac {gt}{c}}+{sqrt {1+left({frac {gt}{c}}right)^{2}}}right)={frac {c}{g}}operatorname {arsinh} left({frac {gt}{c}}right). As functions of the proper time {displaystyle tau }tau of the ship, the following formulae hold:[29]

Position:

{displaystyle x(tau )={frac {c^{2}}{g}}left(cosh {frac {gtau }{c}}-1right).}{displaystyle x(tau )={frac {c^{2}}{g}}left(cosh {frac {gtau }{c}}-1right).} Velocity:

{displaystyle v(tau )=ctanh {frac {gtau }{c}}.}{displaystyle v(tau )=ctanh {frac {gtau }{c}}.} Coordinate time as function of proper time:

{displaystyle t(tau )={frac {c}{g}}sinh {frac {gtau }{c}}.}{displaystyle t(tau )={frac {c}{g}}sinh {frac {gtau }{c}}.} Clock hypothesis The clock hypothesis is the assumption that the rate at which a clock is affected by time dilation does not depend on its acceleration but only on its instantaneous velocity. This is equivalent to stating that a clock moving along a path {displaystyle P}P measures the proper time, defined by:

{displaystyle dtau =int _{P}{sqrt {dt^{2}-dx^{2}/c^{2}-dy^{2}/c^{2}-dz^{2}/c^{2}}}}dtau =int _{P}{sqrt {dt^{2}-dx^{2}/c^{2}-dy^{2}/c^{2}-dz^{2}/c^{2}}}. The clock hypothesis was implicitly (but not explicitly) included in Einstein's original 1905 formulation of special relativity. Since then, it has become a standard assumption and is usually included in the axioms of special relativity, especially in the light of experimental verification up to very high accelerations in particle accelerators.[30][31]

Gravitational time dilation Main article: Gravitational time dilation

Time passes more quickly further from a center of gravity, as is witnessed with massive objects (like the Earth) Gravitational time dilation is experienced by an observer that, at a certain altitude within a gravitational potential well, finds that his local clocks measure less elapsed time than identical clocks situated at higher altitude (and which are therefore at higher gravitational potential).

Gravitational time dilation is at play e.g. for ISS astronauts. While the astronauts' relative velocity slows down their time, the reduced gravitational influence at their location speeds it up, although at a lesser degree. Also, a climber's time is theoretically passing slightly faster at the top of a mountain compared to people at sea level. It has also been calculated that due to time dilation, the core of the Earth is 2.5 years younger than the crust.[32] "A clock used to time a full rotation of the earth will measure the day to be approximately an extra 10 ns/day longer for every km of altitude above the reference geoid."[33] Travel to regions of space where extreme gravitational time dilation is taking place, such as near a black hole, could yield time-shifting results analogous to those of near-lightspeed space travel.

Contrarily to velocity time dilation, in which both observers measure the other as aging slower (a reciprocal effect), gravitational time dilation is not reciprocal. This means that with gravitational time dilation both observers agree that the clock nearer the center of the gravitational field is slower in rate, and they agree on the ratio of the difference.

Experimental testing Main article: Experimental testing of time dilation In 1959 Robert Pound and Glen A. Rebka measured the very slight gravitational redshift in the frequency of light emitted at a lower height, where Earth's gravitational field is relatively more intense. The results were within 10% of the predictions of general relativity. In 1964, Pound and J. L. Snider measured a result within 1% of the value predicted by gravitational time dilation.[34] (See Pound–Rebka experiment) In 2010 gravitational time dilation was measured at the earth's surface with a height difference of only one meter, using optical atomic clocks.[22] Combined effect of velocity and gravitational time dilation

Daily time dilation (gain or loss if negative) in microseconds as a function of (circular) orbit radius r = rs/re, where rs is satellite orbit radius and re is the equatorial Earth radius, calculated using the Schwarzschild metric. At r ? 1.497[Note 1] there is no time dilation. Here the effects of motion and reduced gravity cancel. ISS astronauts fly below, whereas GPS and geostationary satellites fly above.[1]

Daily time dilation over circular orbit height split into its components High-accuracy timekeeping, low-Earth-orbit satellite tracking, and pulsar timing are applications that require the consideration of the combined effects of mass and motion in producing time dilation. Practical examples include the International Atomic Time standard and its relationship with the Barycentric Coordinate Time standard used for interplanetary objects.

Relativistic time dilation effects for the solar system and the earth can be modeled very precisely by the Schwarzschild solution to the Einstein field equations. In the Schwarzschild metric, the interval {displaystyle dt_{text{E}}}{displaystyle dt_{text{E}}} is given by[36][37]

{displaystyle dt_{text{E}}^{2}=left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)dt_{text{c}}^{2}-left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)^{-1}{frac {dx^{2}+dy^{2}+dz^{2}}{c^{2}}},}dt_{text{E}}^{2}=left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)dt_{text{c}}^{2}-left(1-{frac {2GM_{text{i}}}{r_{text{i}}c^{2}}}right)^{-1}{frac {dx^{2}+dy^{2}+dz^{2}}{c^{2}}}, where

{displaystyle dt_{text{E}}}{displaystyle dt_{text{E}}} is a small increment of proper time {displaystyle t_{text{E}}}{displaystyle t_{text{E}}} (an interval that could be recorded on an atomic clock), {displaystyle dt_{text{c}}}{displaystyle dt_{text{c}}} is a small increment in the coordinate {displaystyle t_{text{c}}}{displaystyle t_{text{c}}} (coordinate time), {displaystyle dx,dy,dz}{displaystyle dx,dy,dz} are small increments in the three coordinates {displaystyle x,y,z}x, y, z of the clock's position, {displaystyle {frac {GM_{i}}{r_{i}}}}{displaystyle {frac {GM_{i}}{r_{i}}}} represents the sum of the Newtonian gravitational potentials due to the masses in the neighborhood, based on their distances {displaystyle r_{i}}r_{i} from the clock. This sum includes any tidal potentials. The coordinate velocity of the clock is given by

{displaystyle v^{2}={frac {dx^{2}+dy^{2}+dz^{2}}{dt_{text{c}}^{2}}}.,}v^{2}={frac {dx^{2}+dy^{2}+dz^{2}}{dt_{text{c}}^{2}}}., The coordinate time {displaystyle t_{c}}t_c is the time that would be read on a hypothetical "coordinate clock" situated infinitely far from all gravitational masses ({displaystyle U=0}U=0), and stationary in the system of coordinates ({displaystyle v=0}v=0). The exact relation between the rate of proper time and the rate of coordinate time for a clock with a radial component of velocity is

{displaystyle {frac {dt_{text{E}}}{dt_{text{c}}}}={sqrt {1-{frac {2U}{c^{2}}}-{frac {v^{2}}{c^{2}}}-left({frac {c^{2}}{2U}}-1right)^{-1}{frac {{v_{shortparallel }}^{2}}{c^{2}}}}}={sqrt {1-left(beta ^{2}+beta _{e}^{2}+{frac {beta _{shortparallel }^{2}beta _{e}^{2}}{1-beta _{e}^{2}}}right)}},}{displaystyle {frac {dt_{text{E}}}{dt_{text{c}}}}={sqrt {1-{frac {2U}{c^{2}}}-{frac {v^{2}}{c^{2}}}-left({frac {c^{2}}{2U}}-1right)^{-1}{frac {{v_{shortparallel }}^{2}}{c^{2}}}}}={sqrt {1-left(beta ^{2}+beta _{e}^{2}+{frac {beta _{shortparallel }^{2}beta _{e}^{2}}{1-beta _{e}^{2}}}right)}},} where

{displaystyle v_{shortparallel }}{displaystyle v_{shortparallel }} is the radial velocity, {displaystyle v_{e}={sqrt {frac {2GM_{i}}{r_{i}}}}}{displaystyle v_{e}={sqrt {frac {2GM_{i}}{r_{i}}}}} is the escape velocity, {displaystyle beta =v/c}beta = v/c, {displaystyle beta _{e}=v_{e}/c}{displaystyle beta _{e}=v_{e}/c} and {displaystyle beta _{shortparallel }=v_{shortparallel }/c}{displaystyle beta _{shortparallel }=v_{shortparallel }/c} are velocities as a percentage of speed of light c, {displaystyle U={frac {GM_{i}}{r_{i}}}}{displaystyle U={frac {GM_{i}}{r_{i}}}} is the Newtonian potential, equivalent to half of the escape velocity squared. The above equation is exact under the assumptions of the Schwarzschild solution. It reduces to velocity time dilation equation in the presence of motion and absence of gravity, i.e. {displaystyle beta _{e}=0}{displaystyle beta _{e}=0}. It reduces to gravitational time dilation equation in the absence of motion and presence of gravity, i.e. {displaystyle beta =0=beta _{shortparallel }}{displaystyle beta =0=beta _{shortparallel }}.

Experimental testing Hafele and Keating, in 1971, flew caesium atomic clocks east and west around the Earth in commercial airliners, to compare the elapsed time against that of a clock that remained at the U.S. Naval Observatory. Two opposite effects came into play. The clocks were expected to age more quickly (show a larger elapsed time) than the reference clock, since they were in a higher (weaker) gravitational potential for most of the trip (c.f. Pound–Rebka experiment). But also, contrastingly, the moving clocks were expected to age more slowly because of the speed of their travel. From the actual flight paths of each trip, the theory predicted that the flying clocks, compared with reference clocks at the U.S. Naval Observatory, should have lost 40±23 nanoseconds during the eastward trip and should have gained 275±21 nanoseconds during the westward trip. Relative to the atomic time scale of the U.S. Naval Observatory, the flying clocks lost 59±10 nanoseconds during the eastward trip and gained 273±7 nanoseconds during the westward trip (where the error bars represent standard deviation).[38] In 2005, the National Physical Laboratory in the United Kingdom reported their limited replication of this experiment.[39] The NPL experiment differed from the original in that the caesium clocks were sent on a shorter trip (London–Washington, D.C. return), but the clocks were more accurate. The reported results are within 4% of the predictions of relativity, within the uncertainty of the measurements. The Global Positioning System can be considered a continuously operating experiment in both special and general relativity. The in-orbit clocks are corrected for both special and general relativistic time dilation effects as described above, so that (as observed from the earth's surface) they run at the same rate as clocks on the surface of the Earth.[40] icon Physics portal See also Length contraction Mass in special relativity Footnotes Average time dilation has a weak dependence on the orbital inclination angle (Ashby 2003, p.32). The r ? 1.497 result corresponds to[35] the orbital inclination of modern GPS satellites, which is 55 degrees. References Ashby, Neil (2003). "Relativity in the Global Positioning System" (PDF). Living Reviews in Relativity. 6 (1): 16. Bibcode:2003LRR.....6....1A. doi:10.12942/lrr-2003-1. PMC 5253894. PMID 28163638. Lu, Ed. "Expedition 7: Relativity". Ed's Musing from Space. NASA. Retrieved 2018-04-08. "Is time travel possible?". NASA Space Place. Retrieved 2018-08-03. Miller, Arthur I. (1981). Albert Einstein's Special Theory of Relativity: Emergence (1905) and Early Interpretation (1905–1911). Reading, Massachusetts: Addison–Wesley. ISBN 978-0-201-04679-3.. Darrigol, Olivier (2005). The Genesis of the Theory of Relativity (PDF). Séminaire Poincaré. 1. pp. 1–22. doi:10.1007/3-7643-7436-5_1. ISBN 978-3-7643-7435-8. Larmor, Joseph (1897). "On a Dynamical Theory of the Electric and Luminiferous Medium, Part 3, Relations with Material Media" . Philosophical Transactions of the Royal Society. 190: 205–300. Bibcode:1897RSPTA.190..205L. doi:10.1098/rsta.1897.0020. Cohn, Emil (1904), "Zur Elektrodynamik bewegter Systeme II" [On the Electrodynamics of Moving Systems II], Sitzungsberichte der Königlich Preussischen Akademie der Wissenschaften, 1904/2 (43): 1404–1416 Einstein, Albert (1905). "Zur Elektrodynamik bewegter Körper". Annalen der Physik. 322 (10): 891–921. Bibcode:1905AnP...322..891E. doi:10.1002/andp.19053221004.. See also: English translation. Minkowski, Hermann (1908) [1907], "Die Grundgleichungen für die elektromagnetischen Vorgänge in bewegten Körpern" [The Fundamental Equations for Electromagnetic Processes in Moving Bodies], Nachrichten von der Gesellschaft der Wissenschaften zu Göttingen, Mathematisch-Physikalische Klasse: 53–111 Hraskó, Péter (2011). Basic Relativity: An Introductory Essay (illustrated ed.). Springer Science & Business Media. p. 60. ISBN 978-3-642-17810-8. Extract of page 60 Calder, Nigel (2006). Magic Universe: A grand tour of modern science. Oxford University Press. p. 378. ISBN 978-0-19-280669-7. Overbye, Dennis (2005-06-28). "A Trip Forward in Time. Your Travel Agent: Einstein". The New York Times. Retrieved 2015-12-08. Gott, J., Richard (2002). Time Travel in Einstein's Universe. p. 75. Cassidy, David C.; Holton, Gerald James; Rutherford, Floyd James (2002). Understanding Physics. Springer-Verlag. p. 422. ISBN 978-0-387-98756-9. Cutner, Mark Leslie (2003). Astronomy, A Physical Perspective. Cambridge University Press. p. 128. ISBN 978-0-521-82196-4. Lerner, Lawrence S. (1996). Physics for Scientists and Engineers, Volume 2. Jones and Bartlett. pp. 1051–1052. ISBN 978-0-7637-0460-5. Ellis, George F. R.; Williams, Ruth M. (2000). Flat and Curved Space-times (2n ed.). Oxford University Press. pp. 28–29. ISBN 978-0-19-850657-7. Adams, Steve (1997). Relativity: An introduction to space-time physics. CRC Press. p. 54. ISBN 978-0-7484-0621-0. Blaszczak, Z. (2007). Laser 2006. Springer. p. 59. ISBN 978-3540711131. Hasselkamp, D.; Mondry, E.; Scharmann, A. (1979). "Direct observation of the transversal Doppler-shift". Zeitschrift für Physik A. 289 (2): 151–155. Bibcode:1979ZPhyA.289..151H. doi:10.1007/BF01435932. Einstein, A. (1905). "On the electrodynamics of moving bodies". Fourmilab. Chou, C. W.; Hume, D. B.; Rosenband, T.; Wineland, D. J. (2010). "Optical Clocks and Relativity". Science. 329 (5999): 1630–1633. Bibcode:2010Sci...329.1630C. doi:10.1126/science.1192720. PMID 20929843. Stewart, J. V. (2001). Intermediate electromagnetic theory. World Scientific. p. 705. ISBN 978-981-02-4470-5. Bailey, J. et al. Nature 268, 301 (1977) Edwin F. Taylor, John Archibald Wheeler (1992). Spacetime Physics: Introduction to Special Relativity. New York: W. H. Freeman. ISBN 978-0-7167-2327-1. Born, Max (1964), Einstein's Theory of Relativity, Dover Publications, ISBN 978-0-486-60769-6 Petkov, Vesselin (2009). Relativity and the Nature of Spacetime (2nd, illustrated ed.). Springer Science & Business Media. p. 87. ISBN 978-3-642-01962-3. Extract of page 87 See equations 3, 4, 6 and 9 of Iorio, Lorenzo (2005). "An analytical treatment of the Clock Paradox in the framework of the Special and General Theories of Relativity". Foundations of Physics Letters. 18 (1): 1–19. arXiv:physics/0405038. Bibcode:2005FoPhL..18....1I. doi:10.1007/s10702-005-2466-8. Rindler, W. (1977). Essential Relativity. Springer. pp. 49–50. ISBN 978-3540079705. Bailey, H.; Borer, K.; Combley F.; Drumm H.; Krienen F.; Lange F.; Picasso E.; Ruden W. von; Farley F. J. M.; Field J. H.; Flegel W. & Hattersley P. M. (1977). "Measurements of relativistic time dilatation for positive and negative muons in a circular orbit". Nature. 268 (5618): 301–305. Bibcode:1977Natur.268..301B. doi:10.1038/268301a0. Roos, C. E.; Marraffino, J.; Reucroft, S.; Waters, J.; Webster, M. S.; Williams, E. G. H. (1980). "?+/- lifetimes and longitudinal acceleration". Nature. 286 (5770): 244–245. Bibcode:1980Natur.286..244R. doi:10.1038/286244a0. "New calculations show Earth's core is much younger than thought". Phys.org. 26 May 2016. Burns, M. Shane; Leveille, Michael D.; Dominguez, Armand R.; Gebhard, Brian B.; Huestis, Samuel E.; Steele, Jeffrey; Patterson, Brian; Sell, Jerry F.; Serna, Mario; Gearba, M. Alina; Olesen, Robert; O'Shea, Patrick; Schiller, Jonathan (18 September 2017). "Measurement of gravitational time dilation: An undergraduate research project". American Journal of Physics. 85 (10): 757–762. arXiv:1707.00171. doi:10.1119/1.5000802. Pound, R. V.; Snider J. L. (November 2, 1964). "Effect of Gravity on Nuclear Resonance". Physical Review Letters. 13 (18): 539–540. Bibcode:1964PhRvL..13..539P. doi:10.1103/PhysRevLett.13.539. Ashby, Neil (2002). "Relativity in the Global Positioning System". Physics Today. 55 (5): 45. Bibcode:2002PhT....55e..41A. doi:10.1063/1.1485583. See equations 2 & 3 (combined here and divided throughout by c2) at pp. 35–36 in Moyer, T. D. (1981). "Transformation from proper time on Earth to coordinate time in solar system barycentric space-time frame of reference". Celestial Mechanics. 23 (1): 33–56. Bibcode:1981CeMec..23...33M. doi:10.1007/BF01228543. hdl:2060/19770007221. A version of the same relationship can also be seen at equation 2 in Ashbey, Neil (2002). "Relativity and the Global Positioning System" (PDF). Physics Today. 55 (5): 45. Bibcode:2002PhT....55e..41A. doi:10.1063/1.1485583. Nave, C. R. (22 August 2005). "Hafele and Keating Experiment". HyperPhysics. Retrieved 2013-08-05. "Einstein" (PDF). Metromnia. National Physical Laboratory. 2005. pp. 1–4. Kaplan, Elliott; Hegarty, Christopher (2005). Understanding GPS: Principles and Applications. Artech House. p. 306. ISBN 978-1-58053-895-4. Extract of page 306 Further reading Callender, C.; Edney, R. (2001). Introducing Time. Icon Books. ISBN 978-1-84046-592-1. Einstein, A. (1905). "Zur Elektrodynamik bewegter Körper". Annalen der Physik. 322 (10): 891. Bibcode:1905AnP...322..891E. doi:10.1002/andp.19053221004. Einstein, A. (1907). "Über die Möglichkeit einer neuen Prüfung des Relativitätsprinzips". Annalen der Physik. 328 (6): 197–198. Bibcode:1907AnP...328..197E. doi:10.1002/andp.19073280613. Hasselkamp, D.; Mondry, E.; Scharmann, A. (1979). "Direct Observation of the Transversal Doppler-Shift". Zeitschrift für Physik A. 289 (2): 151–155. Bibcode:1979ZPhyA.289..151H. doi:10.1007/BF01435932. Ives, H. E.; Stilwell, G. R. (1938). "An experimental study of the rate of a moving clock". Journal of the Optical Society of America. 28 (7): 215–226. doi:10.1364/JOSA.28.000215. Ives, H. E.; Stilwell, G. R. (1941). "An experimental study of the rate of a moving clock. II". Journal of the Optical Society of America. 31 (5): 369–374. doi:10.1364/JOSA.31.000369. Joos, G. (1959). "Bewegte Bezugssysteme in der Akustik. Der Doppler-Effekt". Lehrbuch der Theoretischen Physik, Zweites Buch (11th ed.). Larmor, J. (1897). "On a dynamical theory of the electric and luminiferous medium". Philosophical Transactions of the Royal Society. 190: 205–300. Bibcode:1897RSPTA.190..205L. doi:10.1098/rsta.1897.0020. (third and last in a series of papers with the same name). Poincaré, H. (1900). "La théorie de Lorentz et le principe de Réaction". Archives Néerlandaises. 5: 253–78. Puri, A. (2015). "Einstein versus the simple pendulum formula: does gravity slow all clocks?". Physics Education. 50 (4): 431. Bibcode:2015PhyEd..50..431P. doi:10.1088/0031-9120/50/4/431. Reinhardt, S.; et al. (2007). "Test of relativistic time dilation with fast optical atomic clocks at different velocities" (PDF). Nature Physics. 3 (12): 861–864. Bibcode:2007NatPh...3..861R. doi:10.1038/nphys778. Archived from the original (PDF) on 2009-07-12. Rossi, B.; Hall, D. B. (1941). "Variation of the Rate of Decay of Mesotrons with Momentum". Physical Review. 59 (3): 223. Bibcode:1941PhRv...59..223R. doi:10.1103/PhysRev.59.223. Weiss, M. "Two way time transfer for satellites". National Institute of Standards and Technology. Archived from the original on 2017-05-29. Voigt, W. (1887). "Über das Doppler'sche princip". Nachrichten von der Königlicher Gesellschaft der Wissenschaften zu Göttingen. 2: 41–51. External links Merrifield, Michael. "Lorentz Factor (and time dilation)". Sixty Symbols. Brady Haran for the University of Nottingham. vte Time vte Time measurement and standards vte Relativity Categories: Special relativityTime in physicsConcepts in physics Navigation menu Not logged inTalkContributionsCreate accountLog inArticleTalkReadEditView historySearch Search Wikipedia Main page Contents Featured content Current events Random article Donate to Wikipedia Wikipedia store Interaction Help About Wikipedia Community portal Recent changes Contact page Tools What links here Related changes Upload file Special pages Permanent link Page information Wikidata item Cite this page In other projects Wikimedia Commons Print/export Download as PDF Printable version

Languages ??????? Español Bahasa Indonesia Bahasa Melayu Português ??????? ?????????? ???? ?? 37 more Edit links This page was last edited on 11 January 2020, at 10:05 (UTC). Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-pro

View Details

The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)The Moral Self (Jesse Prinz)

View Details

antichrist_01_nietzsche_64kb.mp3 subido cantichrist_01_nietzsche_64kb.mp3 subido cantichrist_01_nietzsche_64kb.mp3 subido cantichrist_01_nietzsche_64kb.mp3 subido cantichrist_01_nietzsche_64kb.mp3 subido cantichrist_01_nietzsche_64kb.mp3 subido cantichrist_01_nietzsche_64kb.mp3 subido cantichrist_01_nietzsche_64kb.mp3 subido cantichrist_01_nietzsche_64kb.mp3 subido c

View Details

12 nietzsche on truth and interpretation.mp3 subido correctamente

12 nietzsche on truth and interpretation.mp3 subido correctamente

12 nietzsche on truth and interpretation.mp3 subido correctamente

12 nietzsche on truth and interpretation.mp3 subido correctamente

12 nietzsche on truth and interpretation.mp3 subido correctamente

View Details

.mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido .mp3 subido