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arXiv · 0708.1334

A Proof that Thompson's Groups have Infinitely Many Relative Ends

Daniel Farley
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Abstract

We show that each of Thompson's groups F, T, and V have infinitely many ends relative to certain subgroups. We go on to show that T and V both have Serre's property FA, i.e., any action of T or V on a tree will have a fixed point. (The proof of the latter statement was originally due to Ken Brown, and our proof is based on his notes.)

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Daniel Farley. 2007-08-09. A Proof that Thompson's Groups have Infinitely Many Relative Ends. https://arxiv.org/abs/0708.1334

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