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Re:Church-Turing Thesis Cannot Possibly Be True [video] by macleginn on Friday October 19, 2018 @04:56AM (#18255225)
As was proved recently, there are quantum algorithms that can not: https://www.quantamagazine.org/finally-a-problem-that-only-q...
Re:Church-Turing Thesis Cannot Possibly Be True [video] by atq2119 on Friday October 19, 2018 @05:27AM (#18255376)
First of all, the paper that this article is reporting on doesn't actually prove a separation between quantum and classical algorithms at all. It's an oracle separation result, which makes it an important result in complexity theory, but not a statement about actual classical or quantum algorithms.

Second, the result is unrelated to the Church-Turing thesis in the first place, since it's only about relative efficiency, whereas the Church-Turing thesis is about computability.

Every quantum algorithm can be simulated by a classical computer, so quantum computing cannot possibly disprove the Church-Turing thesis. However, there's a stronger variant of the Church-Turing thesis which also takes performance into account, and it's plausible that quantum computers can contradict this stronger version (although we're very far away from actually proving that).