Videos

Three proofs from dynamics of rigidity of surface group actions

Presenter
April 15, 2015
Keywords:
  • surface group
  • rigidity results
  • discrete subgroups
  • folations, leaves
  • Hitchin representation
  • geometric actions
MSC:
  • 37D20
  • 37Dxx
  • 37-xx
  • 30F60
  • 30Fxx
  • 53D18
  • 53C24
  • 53Cxx
  • 53C12
  • 53-xx
Abstract
In previous talks (not a prerequisite!), I've described examples of actions of a surface group G on the circle that are totally rigid -- they are essentially isolated points in the representation space Hom(G, Homeo+(S^1))/~. These examples are interesting from many perspectives, ranging from foliation theory to the classification of connected components of representation spaces. In this talk, I will illustrate three separate approaches to prove rigidity of these actions, including my original proof. Each one uses fundamentally different techniques, but all have a common dynamical flavor: 1. Structural stability of Anosov foliations (Ghys/Bowden, under extra hypotheses) 2. Rotation number "trace coordinates" on the representation space (Mann) 3. New "ping-pong" lemmas for surface groups (Matsumoto)
Supplementary Materials