Videos

Superintrinsic synthesis in fixed point properties

Presenter
December 8, 2016
Keywords:
  • fixed point properties
  • property (T)
  • property t
  • expander graph
  • bounded generation
  • hyperbolic groups and generalizations
  • Banach space
  • group cohomology
  • index theory
  • non-commutative geometry
MSC:
  • 37A15
  • 19-xx
  • 20-xx
  • 43-xx
  • 46-xx
  • 57-xx
  • 58-xx
  • 20F65
  • 46L80
  • 20J06
  • 43A07
Abstract
The following natural question arises from Shalom's innovational work (1999, Publ.IHES) on Kazhdan's property (T). ``Can we establish an `intrinsic' criterion to synthesize relative fixed point properties into the whole fixed point property without assuming `Bounded Generation'?'' This talk is aimed to present a resolution to this question in the affirmative. Our criterion works for ones with respect to certain classes of Busemann Non-Positively Curved spaces. It, moreover, suggests a further step toward constructing super-expanders from finite simple groups of Lie type.