Abstract: 
The talks will center around the articles: Boundaries of reduced C*algebras of discrete groups by Kalantar–Kennedy, and C*simplicity and the unique trace property for discrete groups by Breuillard–Kalantar–Kennedy–Ozawa. We will also cover background material on C*algebras, C*simplicity and Furstenberg boudaries. A detailed programme is available here. 


Framework: 
This activity belongs to the IAP project DYGEST.

Organisers: 
PierreEmmanuel Caprace and Stefaan Vaes 
[BKKO]  E. Breuillard, M. Kalantar, M. Kennedy and N. Ozawa, C*simplicity and the unique trace property for discrete groups, arXiv. 
[dlH1]  P. de la Harpe, Reduced C*algebras of discrete groups which are simple with a unique trace. In Operator algebras and their connections with topology and ergodic theory (Busteni, 1983). Lecture Notes in Mathematics 1132, Springer, Berlin, 1985, pp. 230–253. 
[dlH2]  P. de la Harpe, On simplicity of reduced C*algebras of groups, Bull. London Math. Soc. 39 (2007), 1–26. 
[Fu]  A. Furman, On minimal strongly proximal actions of locally compact groups, Israel J. Math. 136 (2003), 173–187. 
[KK]  M. Kalantar and M. Kennedy, Boundaries of reduced C*algebras of discrete groups, arXiv. 
[Oz]  N. Ozawa, Lectures on the Furstenberg boundary and C*simplicity, available here. 
10:00  Stefaan Vaes (KUL): Introduction to C*algebras and C*simplicity 


11:30  François Le Maître (UCL): The Powers property 
14:00  PierreEmmanuel Caprace (UCL): Furstenberg boundaries 


15:30  Stefaan Vaes (KUL): Hamana boundaries 
14:00  Tim de Laat (KUL): C*simplicity and topologically free boundary actions 


15:30  Peter Verraedt (KUL): C*simplicity and normalish amenable subgroups 
14:00  David Hume (UCL): C*simplicity, bounded cohomology and ℓ^{2}Betti numbers 


15:30  Phillip Wesolek (UCL): C*simplicity for linear groups 
14:00  Adrien Le Boudec (UCL): NonC*simple discrete groups with trivial amenable radical 