Abstract: A countable group is C*-simple if its reduced C*-algebra is simple. We will first survey recent results of Kalentar-Kennedy and Breuillard-Kalentar-Kennedy-Ozawa about the connection between the C*-simplicity of a countable group and its boundary actions. We will then explain the construction of non-C*-simple groups with no amenable normal subgroup. Some examples arising from this construction are moreover finitely generated and simple.
C*-simplicity and the amenable radical (GGT-Seminar)
SR 1.067 (20.30)
Adrien Le Boudec