Abstract: In the 1970s G.A.Margulis proved that linear representations of certain discrete subgroups (namely lattices) in such Lie groups as SL(3,R), are essentially determined by the ambient Lie group. This phenomenon, known as superrigidity, has far reaching applications and has inspired a large body of research in such areas as geometry, dynamics, descriptive set theory, operator algebras etc.

We shall try to explain the superrigidity of lattices and related groups by looking at some hidden symmetries (Weyl group) that they inherit from the ambient group.

The talk is based on a joint work with Uri Bader.

Coffee will be served at 12:00 before the lecture
at Schreiber building 006