07/06: Rémi Boutonnet
On the unitary dual of higher rank semi-simple lattices
Abstract: In this talk, based on joint work with Cyril Houdayer, I
will present a curious property of the unitary representations of
lattices in semi-simple higher rank Lie groups: either they contain a
finite dimensional invariant subspace or they are factorizations of
the regular representation, in a strong sense. I will explain how this
result generalizes and unifies recent advances in operator algebras.
Our approach relies on ergodic theory and stationary dynamical
systems.