• Corpus ID: 208164626

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… 

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