English

Folner tilings for actions of amenable groups

Dynamical Systems 2020-01-20 v2 Group Theory Operator Algebras

Abstract

We show that every probability-measure-preserving action of a countable amenable group G can be tiled, modulo a null set, using finitely many finite subsets of G ("shapes") with prescribed approximate invariance so that the collection of tiling centers for each shape is Borel. This is a dynamical version of the Downarowicz--Huczek--Zhang tiling theorem for countable amenable groups and strengthens the Ornstein--Weiss Rokhlin lemma. As an application we prove that, for every countably infinite amenable group G, the crossed product of a generic free minimal action of G on the Cantor set is Z-stable.

Keywords

Cite

@article{arxiv.1704.00699,
  title  = {Folner tilings for actions of amenable groups},
  author = {Clinton T. Conley and Steve Jackson and David Kerr and Andrew Marks and Brandon Seward and Robin Tucker-Drob},
  journal= {arXiv preprint arXiv:1704.00699},
  year   = {2020}
}

Comments

Minor revisions. Final version

R2 v1 2026-06-22T19:06:14.034Z