Videos

Lp-compression of wreath products and some related groups

Presenter
December 9, 2016
Keywords:
  • wreath product
  • Lp-compression
  • amenable groups
  • a-T-menability
  • fixed point properties
  • hyperbolic groups and generalizations
  • Banach space
  • group cohomology
  • expander graph
  • index theory
  • non-commutative geometry
MSC:
  • 20F65
  • 22D10
  • 20-xx
  • 43-xx
  • 46-xx
  • 57-xx
  • 58-xx
  • 19-xx
  • 46L80
  • 20J06
  • 43A07
Abstract
We show a formula relating the L_p-compression exponent of a group and its wreath product with a cyclic group for p in [1, 2]. The argument extends the Markov type method introduced by Naor and Peres. Using wreath product as ingredients, we construct finitely generated amenable groups with arbitrary prescribed L_p compression exponent in the interval [0,1]. This can be viewed as an elementary amenable analogue of a result of Arzhantseva, Drutu and Sapir. Joint with Jeremie Brieussel