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arXiv · 1307.5002

Inner amenability for groups and central sequences in factors

Ionut Chifan·Thomas Sinclair·Bogdan Udrea
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Abstract

We show that a large class of i.c.c., countable, discrete groups satisfying a weak negative curvature condition are not inner amenable. By recent work of Hull and Osin, our result recovers that mapping class groups and Out(F_n) are not inner amenable. We also show that the group-measure space constructions associated to free, strongly ergodic p.m.p. actions of such groups do not have property Gamma of Murray and von Neumann.

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Ionut Chifan, Thomas Sinclair, Bogdan Udrea. 2013-07-18. Inner amenability for groups and central sequences in factors. https://doi.org/10.1017/etds.2014.91

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