English

The boundary action of a sofic random subgroup of the free group

Dynamical Systems 2014-11-27 v2

Abstract

We prove that the boundary action of a sofic random subgroup of a finitely generated free group is conservative. This addresses a question asked by Grigorchuk, Kaimanovich, and Nagnibeda, who studied the boundary actions of individual subgroups of the free group. Following their work, we also investigate the cogrowth and various limit sets associated to sofic random subgroups. We make heavy use of the correspondence between subgroups and their Schreier graphs, and central to our approach is an investigation of the asymptotic density of a given set inside of large neighborhoods of the root of a sofic random Schreier graph.

Keywords

Cite

@article{arxiv.1306.1444,
  title  = {The boundary action of a sofic random subgroup of the free group},
  author = {Jan Cannizzo},
  journal= {arXiv preprint arXiv:1306.1444},
  year   = {2014}
}

Comments

21 pages, 2 figures, made minor corrections, to appear in Groups, Geometry, and Dynamics