I promise you: this post is going to tell a scientifically coherent story that involves all five topics listed in the title. Not one can be omitted. My story starts with a Zoom talk that the one and only Lenny Susskind delivered for the Simons Institute for Theory of Computing back in May. There followed … Continue reading On black holes, holography, the Quantum Extended Church-Turing Thesis, fully homomorphic encryption, and brain uploading