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arXiv · 0903.0648

Tilings and Submonoids of Metabelian Groups

Markus Lohrey·Benjamin Steinberg
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Abstract

In this paper we show that membership in finitely generated submonoids is undecidable for the free metabelian group of rank 2 and for the wreath product $\mathbb Z\wr (\mathbb Z\times \mathbb Z)$. We also show that subsemimodule membership is undecidable for finite rank free $(\mathbb Z\times \mathbb Z)$-modules. The proof involves an encoding of Turing machines via tilings. We also show that rational subset membership is undecidable for two-dimensional lamplighter groups.

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Markus Lohrey, Benjamin Steinberg. 2009-03-03. Tilings and Submonoids of Metabelian Groups. https://arxiv.org/abs/0903.0648

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