An inner amenable group whose von Neumann algebra does not have property Gamma

Stefaan Vaes

doi:10.1007/s11511-012-0079-1

2012 An inner amenable group whose von Neumann algebra does not have property Gamma

Stefaan Vaes

Author Affiliations +

Acta Math. 208(2): 389-394 (2012). DOI: 10.1007/s11511-012-0079-1

Abstract

We construct inner amenable groups G with infinite conjugacy classes and such that the associated II₁ factor has no non-trivial asymptotically central elements, i.e. does not have property Gamma of Murray and von Neumann. This solves a problem posed by Effros in 1975.

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2012 © Institut Mittag-Leffler

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Stefaan Vaes "An inner amenable group whose von Neumann algebra does not have property Gamma," Acta Mathematica 208(2), 389-394, (2012). https://doi.org/10.1007/s11511-012-0079-1

Received: 18 March 2010; Published: 2012

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