Quantum Computing since Democritus

by Scott Aaronson

Schrödinger was interested in a lot of things. He was not an intellectual monogamist (or really any kind of monogamist).

You can think of advice as freeze-dried computation. There's some great, enormous sort of computational effort, that we then encapsulate in this convenient polynomially sized string over in the frozen foods section and that you can go and heat into the microwave to do work with.

Shor's algorithm for factoring and discrete log. I’ll assume you've heard of this algorithm, since it was one of the major scientific achievements of the late twentieth century, and is why we're talking about these things in the first place. If you haven't seen it, there are about 500000 expositions on the Web.

But can CTCs actually exist in Nature? This question has a very long history of being studied by physicists on weekends.