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arXiv · 2304.10012

A non-Hopfian relatively hyperbolic group with respect to a Hopfian subgroup

Jan Kim·Donghi Lee
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Abstract

We produce an example demonstrating that every finitely generated relatively hyperbolic group with respect to a collection of Hopfian subgroups need not be Hopfian. This answers a question of Osin \cite[Problem 5.5]{Osin} in the negative.

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Jan Kim, Donghi Lee. 2023-04-19. A non-Hopfian relatively hyperbolic group with respect to a Hopfian subgroup. https://arxiv.org/abs/2304.10012

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