Title: Large forests and Littlewood
2013.11.25 |
Date | Fri 16 Apr |
Time | 14:15 — 15:15 |
Location | Aud D3 |
Abstract:
Motivated by a classical result of Sz.-Nagy in functional analysis, Dixmier asked in 1950 which group representations can be made unitary. This question is still open, but I will report on some progress obtained with Epstein and Ozawa. We approach the question with ideas borrowed from XIXth century electricity theory as well as from contemporary percolation theory. As a result, we obtain notably non-unitarizable representations for Burnside groups and a new characterization of amenability. The talk will be expository.