Examples of groups which are not weakly amenable

Abstract

We prove that weak amenability of a locally compact group imposes a strong condition on its amenable closed normal subgroups. This extends non weak amenability results of Haagerup (1988) and Ozawa--Popa (2010). A von Neumann algebra analogue is also obtained.

10 pages; some remarks are clarified (v2)

References in corpus (1)

• Group C*-algebras without the completely bounded approximation property

Cited by in corpus (21)

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