English

The ratio set of the harmonic measure of a random walk on a hyperbolic group

Dynamical Systems 2007-05-23 v1 Group Theory Operator Algebras Probability

Abstract

We consider the harmonic measure on the Gromov boundary of a nonamenable hyperbolic group defined by a finite range random walk on the group, and study the corresponding orbit equivalence relation on the boundary. It is known to be always amenable and of type III. We determine its ratio set by showing that it is generated by certain values of the Martin kernel. In particular, we show that the equivalence relation is never of type III_0.

Keywords

Cite

@article{arxiv.math/0602409,
  title  = {The ratio set of the harmonic measure of a random walk on a hyperbolic group},
  author = {Masaki Izumi and Sergey Neshveyev and Rui Okayasu},
  journal= {arXiv preprint arXiv:math/0602409},
  year   = {2007}
}

Comments

21 pages