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On Følner sets in topological groups

Published online by Cambridge University Press:  16 May 2018

Friedrich Martin Schneider
Affiliation:
Institute of Algebra, TU Dresden, 01062 Dresden, Germany email [email protected]
Andreas Thom
Affiliation:
Institute of Geometry, TU Dresden, 01062 Dresden, Germany email [email protected]

Abstract

We extend Følner’s amenability criterion to the realm of general topological groups. Building on this, we show that a topological group $G$ is amenable if and only if its left-translation action can be approximated in a uniform manner by amenable actions on the set  $G$ . As applications we obtain a topological version of Whyte’s geometric solution to the von Neumann problem and give an affirmative answer to a question posed by Rosendal.

Type
Research Article
Copyright
© The Authors 2018 

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