Yurii Neretin "On closures of infinite-dimensional groups in unitary representations"

jeudi 29 sept. 2022, 16:00 → 17:00 Europe/Paris

On closures of infinite-dimensional groups in unitary representations

 

Consider a topological group  $G$ and its unitary representation $\rho$.  Consider the closure of $\rho(G)$ in the weak operator topology. Then we  get a compact semigroup with separately continuous multiplication.  The purpose of talk is an introduction to problems of this type for infinite 
dimensional groups. I hope to discuss briefly the similar  problem for measure preserving actions of groups and non-singular actions on measure spaces (we do not suppose any preliminary knowledge of representation 
theory).