Time

Nov 3 2011 - 4:30pm - 5:30 pm

Location

CH 240

Speaker

Hillel Furstenberg (Hebrew Univ. of Jerusalem)

Abstract

The theory of harmonic functions on symmetric spaces leads  naturally to a notion of "boundary" for semi-simple Lie groups. This  can be generalized to general non-compact groups. The boundary turns  out to be useful for providing "laws of large numbers" for independent  random variables in a non-commutative setting. It plays a major role  in a theory of non-measure preserving group actions. We will illustrate this by discussing a "multiple recurrence" phenomenon for so-called "stationary group actions".