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arXiv · 1702.00923

An All-Or-Nothing Flavor to the Church-Turing Hypothesis

Stefan Wolf
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Abstract

Landauer's principle claims that "Information is Physical." It is not surprising that its conceptual antithesis, Wheeler's "It from Bit," has been more popular among computer scientists --- in the form of the Church-Turing hypothesis: All natural processes can be computed by a universal Turing machine; physical laws then become descriptions of subsets of observable, as opposed to merely possible, computations. Switching back and forth between the two traditional styles of thought, motivated by quantum-physical Bell correlations and the doubts they raise about fundamental space-time causality, we look for an intrinsic, physical randomness notion and find one around the second law of thermodynamics. Bell correlations combined with complexity as randomness tell us that beyond-Turing computations are either physically impossible, or they can be carried out by "devices" as simple as individual photons.

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Stefan Wolf. 2017-02-03. An All-Or-Nothing Flavor to the Church-Turing Hypothesis. https://arxiv.org/abs/1702.00923

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