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arXiv · 2107.13250

Volume vs. Complexity of Hyperbolic Groups

Nir Lazarovich
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Abstract

We prove that for a one-ended hyperbolic graph $X$, the size of the quotient $X/G$ by a group $G$ acting freely and cocompactly bounds from below the number of simplices in an Eilenberg-MacLane space for $G$. We apply this theorem to show that one-ended hyperbolic cubulated groups (or more generally, one-ended hyperbolic groups with globally stable cylinders \`a la Rips-Sela) cannot contain isomorphic finite-index subgroups of different indices.

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Nir Lazarovich. 2021-07-28. Volume vs. Complexity of Hyperbolic Groups. https://arxiv.org/abs/2107.13250

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