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arXiv · 1203.3317

An (FA)-group that is not (FR)

Martin J. Dunwoody·Ashot Minasyan
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Abstract

We construct examples of finitely generated groups L that have non-trivial actions on $\mathbb{R}$-trees but which cannot act, without fixing a vertex, on any simplicial tree. Moreover, any finitely presented group mapping onto L does have a fixed point-free action on some simplicial tree.

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Martin J. Dunwoody, Ashot Minasyan. 2013-06-18. An (FA)-group that is not (FR). https://arxiv.org/abs/1203.3317

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