Time: Wednesday, May 21, 2025, 9:00-10:30 (UTC+8)
Venue: Gewu Building, Room 315
Zoom ID: 931 9206 9812 (Password: 721277)
Speaker: Sayan Das (East China Normal University)
Title: Poisson boundaries of groups and von Neumann algebras
Abstract:
Furstenberg introduced the notion of Poisson boundary of groups in 1960s. Since then, Poisson boundaries have played a pivotal role in ergodic theory, and measured group theory to study various rigidity phenomenon associated with groups and their actions.
Motivated by this, Alain Connes proposed that a corresponding notion of Poisson boundaries for von Neumann algebras needs to be developed in order to study rigidity aspects of von Neumann algebras. In this talk, I will explain the notion of classical Poisson boundaries, and their noncommutative counterpart, which was developed by Prof. Jesse Peterson and the speaker. I will also mention a few applications.