How Quantum Computers affect Cryptography and Blockchain

crypto zk quantum || I think this post is a good middle ground between the oversimplified layman-oriented quantum news articles, and the hyper academic quantum computing papers that are hard for a cryptographer to parse. As the field rapidly evolves, things here may become outdated or wrong. Feel free to leave thoughts/comments/corrections on the hackmd draft of this post! An old version was previously also posted on zkresearch. Thanks to Aram Harrow, Krishanu Sankar, and Lev Stambler for comments and discussions – all errors are mine, not theirs.