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arXiv · 1812.07799

Hyperbolic groups that are not commensurably coHopfian

Emily Stark·Daniel J. Woodhouse
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Abstract

Sela proved every torsion-free one-ended hyperbolic group is coHopfian. We prove that there exist torsion-free one-ended hyperbolic groups that are not commensurably coHopfian. In particular, we show that the fundamental group of every simple surface amalgam is not commensurably coHopfian.

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Emily Stark, Daniel J. Woodhouse. 2018-12-19. Hyperbolic groups that are not commensurably coHopfian. https://arxiv.org/abs/1812.07799

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