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arXiv · 2309.13644

Commensurated hyperbolic subgroups

Nir Lazarovich·Alex Margolis·Mahan Mj
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Abstract

We show that if H is a non-elementary hyperbolic commensurated subgroup of infinite index in a hyperbolic group G, then H is virtually a free product of hyperbolic surface groups and free groups. We prove that whenever a one-ended hyperbolic group H is a fiber of a non-trivial hyperbolic bundle then H virtually splits over a 2-ended subgroup.

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Nir Lazarovich, Alex Margolis, Mahan Mj. 2023-09-24. Commensurated hyperbolic subgroups. https://arxiv.org/abs/2309.13644

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