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

Published online by Cambridge University Press:  04 May 2021

ADRIAN IOANA*
Affiliation:
Department of Mathematics, University of California San Diego, 9500 Gilman Drive, La Jolla, CA92093, USA

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.

Type
Original Article
Copyright
© The Author(s), 2021. Published by Cambridge University Press

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