UBC Mathematics Department Colloquium Hosted by PIMS-UBC 2007

  • Date: 01/25/2007
Lecturer(s):

Lior Silberman (Harvard University)

Location: 

University of British Columbia

Topic: 

A discrete group has 'Property (T)' if every isometric (affine) action
of the group on Hilbert space has a global fixed point. This is a
spectral-gap property and was originally defined by Kazhdan to study
lattices in Lie groups. Recently Gromov formulated a probabilistic
model for constructing (T) groups of very differnet character, starting
with graphs with large spectral gaps ('expanders'). I shall describe
the metric geometry approach to fixed point properties, and give two
applications: showing that the 'wild' groups constructed by Gromov have
a much stronger fixed-point property, and an algorithm which enumerates
the finite presentations with property (T).

Other Information: 

UBC Mathematics Department Colloquium Hosted by PIMS-UBC 2007

Sponsor: 

pims