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arXiv · 1611.01741

On commensurability of right-angled Artin groups I: RAAGs defined by trees of diameter 4

Montserrat Casals-Ruiz·Ilya Kazachkov·Alexander Zakharov
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Abstract

In this paper we study the classification of right-angled Artin groups up to commensurability. We characterise the commensurability classes of RAAGs defined by trees of diameter 4. In particular, we prove a conjecture of Behrstock and Neumann that there are infinitely many commensurability classes. Hence, we give first examples of RAAGs that are quasi-isometric but not commensurable.

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Montserrat Casals-Ruiz, Ilya Kazachkov, Alexander Zakharov. 2016-11-06. On commensurability of right-angled Artin groups I: RAAGs defined by trees of diameter 4. https://arxiv.org/abs/1611.01741

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