Acta Mathematica

, Volume 208, Issue 2, pp 389–394 | Cite as

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



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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Copyright information

© Institut Mittag-Leffler 2012

Authors and Affiliations

  1. 1.Department of MathematicsKU LeuvenLeuvenBelgium

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