English

Uniform Local Amenability implies Property A

Metric Geometry 2021-04-20 v3 Combinatorics

Abstract

In this short note we answer a query of Brodzki, Niblo, \v{S}pakula, Willett and Wright by showing that all bounded degree uniformly locally amenable graphs have Property A. For the second result of the note recall that Kaiser proved that if Γ\Gamma is a finitely generated group and {Hi}i=1\{H_i\}^\infty_{i=1} is a Farber sequence of finite index subgroups, then the associated Schreier graph sequence is of Property A if and only if the group is amenable. We show however, that there exist a non-amenable group and a nested sequence of finite index subgroups {Hi}i=1\{H_i\}^\infty_{i=1} such that H={eΓ}\cap H=\{e_\Gamma\}, and the associated Schreier graph sequence is of Property A.

Keywords

Cite

@article{arxiv.1912.00806,
  title  = {Uniform Local Amenability implies Property A},
  author = {Gábor Elek},
  journal= {arXiv preprint arXiv:1912.00806},
  year   = {2021}
}

Comments

to appear in the Proceedings of the American Mathematical Society

R2 v1 2026-06-23T12:33:08.261Z