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On sofic approximations of ${\mathbb F}_2\times {\mathbb F}_2$

Part of: Special aspects of infinite or finite groups Permutation groups

Published online by Cambridge University Press:  04 May 2021

ADRIAN IOANA
ADRIAN IOANA*
Affiliation:
Department of Mathematics, University of California San Diego, 9500 Gilman Drive, La Jolla, CA92093, USA
*
e-mail: aioana@ucsd.edu
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Abstract

We construct a sofic approximation of ${\mathbb F}_2\times {\mathbb F}_2$ that is not essentially a ‘branched cover’ of a sofic approximation by homomorphisms. This answers a question of L. Bowen.

Keywords

sofic groupsofic approximationproperty taugroup stability

MSC classification

Primary: 20B07: General theory for infinite groups
Secondary: 20F69: Asymptotic properties of groups
Type
Original Article
Information
Ergodic Theory and Dynamical Systems , Volume 42 , Issue 7 , July 2022 , pp. 2333 - 2351
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Copyright
© The Author(s), 2021. Published by Cambridge University Press

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