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arXiv · 0910.5732

JSJ decompositions of Coxeter groups over FA subgroups

John Ratcliffe·Steven Tschantz
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Abstract

A group G has property FA if G fixes a point of every tree on which G acts without inversions. We prove that every Coxeter system of finite rank has a visual JSJ decomposition over subgroups with property FA. As an application, we reduce the twist conjecture to Coxeter systems that are indecomposable with respect to amalgamated products over visual subgroups with property FA.

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John Ratcliffe, Steven Tschantz. 2009-10-29. JSJ decompositions of Coxeter groups over FA subgroups. https://arxiv.org/abs/0910.5732

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