Frontiers in Mathematical Sciences 7th Conference University of Isfahan - January 1-3, 2020
 Title: Representation rigidity of subgroups and $C^\star$-algebras of quasi-regular representations Speaker: Mehrdad Kalantar, University of Houston Date, Time, and Venue:  Friday, January 3 | 08:30-09:15 | Hall 1 Abstract: We introduce several equivalence relations on the set of subgroups of a countable group $G$, defined in terms of the quasi-regular representations, and present some rigidity results in terms of those equivalence relations for certain classes of subgroups. Furthermore, we give some results concerning the ideal structure of the $C^\star$-algebras generated by the quasi-regular representations. This is joint work with Bachir Bekka.