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arXiv · 1902.03852

The word problem of the Brin-Thompson group is coNP-complete

J. C. Birget
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Abstract

We prove that the word problem of the Brin-Thompson group nV over a finite generating set is coNP-complete for every n \ge 2. It is known that the groups nV are an infinite family of infinite, finitely presented, simple groups. We also prove that the word problem of the Thompson group V over a certain infinite set of generators, related to boolean circuits, is coNP-complete.

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J. C. Birget. 2019-02-11. The word problem of the Brin-Thompson group is coNP-complete. https://arxiv.org/abs/1902.03852

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