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arXiv · 2412.08140

Relative hyperbolicity of ascending HNN extension of groups

Swathi Krishna
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Abstract

We prove that for a finitely generated group G with a free factor system and an injective endomorphism that preserves the free factor system, the ascending HNN extension of G is hyperbolic relative to a collection of maximal parabolic subgroups. As a corollary, we see that if an injective endomorphism of a finite rank free group F is exponentially growing, the ascending HNN extension of F is relatively hyperbolic.

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Swathi Krishna. 2024-12-11. Relative hyperbolicity of ascending HNN extension of groups. https://arxiv.org/abs/2412.08140

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