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arXiv · 2003.10328

A Physically Universal Turing Machine

Ville Salo·Ilkka Törmä
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Abstract

We construct a two-dimensional Turing machine that is physically universal in both the moving tape and moving head model. In particular, it is mixing of all finite orders in both models. We also provide a variant that is physically universal in the moving tape model, but not in the moving head model.

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Ville Salo, Ilkka Törmä. 2020-03-20. A Physically Universal Turing Machine. https://arxiv.org/abs/2003.10328

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