Amenable actions and exactness for discrete groups
Operator Algebras
2009-10-31 v2 Functional Analysis
Abstract
It is proved that a discrete group G is exact if and only if its left translation action on the Stone-Cech compactification is amenable. Combining this with an unpublished result of Gromov, we have the existence of non exact discrete groups.
Cite
@article{arxiv.math/0002185,
title = {Amenable actions and exactness for discrete groups},
author = {Narutaka Ozawa},
journal= {arXiv preprint arXiv:math/0002185},
year = {2009}
}
Comments
Added remarks and a reference. Submitted to Comptes Rendus Acad. Sci. Paris