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Mathematische Annalen

, Volume 346, Issue 4, pp 969–989 | Cite as

Strongly solid group factors which are not interpolated free group factors

  • Cyril HoudayerEmail author
Article

Abstract

We give examples of non-amenable infinite conjugacy classes groups Γ with the Haagerup property, weakly amenable with constant Λcb(Γ) = 1, for which we show that the associated II1 factors L(Γ) are strongly solid, i.e. the normalizer of any diffuse amenable subalgebra \({P \subset L(\Gamma)}\) generates an amenable von Neumann algebra. Nevertheless, for these examples of groups Γ, L(Γ) is not isomorphic to any interpolated free group factor L(F t ), for 1 < t ≤  ∞.

Mathematics Subject Classification (2000)

Primary 46L10 46L54 Secondary 22D25 37A20 

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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  1. 1.CNRS-ENS LyonLyon cedex 7France

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