Cryptocurrency. What is it? What about currency? Is the answer more or less centralized banking? Here's some facts.

Lengths of Ancient Empires - https://owlcation.com/humanities/How-long-do-empires-last

How Bitcoin Works - https://youtu.be/t5JGQXCTe3c

Etherium Classic 51% Attack - https://cointelegraph.com/news/ethereum-classic-51-attack-the-reality-of-proof-of-work

JP Morgan Rolling Out Cryptocurrency - https://www.nytimes.com/2019/02/14/business/dealbook/jpmorgan-cryptocurrency-bitcoin.html