Boundary actions, germs and quasi-regular representations
Eduardo Scarparo (Federal University of Santa Catarina, Brazil)
Thursday 20th January 16:00-17:00 Maths 311B
We will present applications of boundary actions to the investigation of the ideal and tracial structure of C*-algebras generated by unitary representations. In particular, for quasi-regular representations associated to stabilizers of boundary actions we have a complete understanding of the trace space of such C*-algebras and when they are simple. We will also show that the groupoid of germs of the action of Thompson's group T on S^1 is non-Hausdorff, and its essential C*-algebra is a possible example of Kirchberg algebra without Cartan subalgebra.