Undecidable word problem in subshift automorphism groups

Pierre Guillon; Emmanuel Jeandel; Jarkko Kari; Pascal Vanier

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arXiv · 1808.09194

Undecidable word problem in subshift automorphism groups

Pierre Guillon·Emmanuel Jeandel·Jarkko Kari·Pascal Vanier

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Abstract

This article studies the complexity of the word problem in groups of automorphisms of subshifts. We show in particular that for any Turing degree, there exists a subshift whose automorphism group contains a subgroup whose word problem has exactly this degree.

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Pierre Guillon, Emmanuel Jeandel, Jarkko Kari, Pascal Vanier. 2018-08-28. Undecidable word problem in subshift automorphism groups. https://arxiv.org/abs/1808.09194

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