# SUBGROUP DYNAMICS AND C∗-SIMPLICITY OF GROUPS OF HOMEOMORPHISMS

@inproceedings{Boudec2016SUBGROUPDA, title={SUBGROUP DYNAMICS AND C∗-SIMPLICITY OF GROUPS OF HOMEOMORPHISMS}, author={Adrien Le Boudec}, year={2016} }

We study the uniformly recurrent subgroups of groups acting by homeomorphisms on a topological space. We prove a general result relating uniformly recurrent subgroups to rigid stabilizers of the action, and deduce a C∗-simplicity criterion based on the non-amenability of rigid stabilizers. As an application, we show that Thompson’s group V is C∗-simple, as well as groups of piecewise projective homeomorphisms of the real line. This provides examples of finitely presented C∗-simple groups…

## 36 Citations

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