Kyoto Journal of Mathematics

Examples of groups which are not weakly amenable

Narutaka Ozawa

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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 and Popa (2010). A von Neumann algebra analogue is also obtained.

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Kyoto J. Math. Volume 52, Number 2 (2012), 333-344.

First available in Project Euclid: 24 April 2012

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Zentralblatt MATH identifier

Primary: 43A22: Homomorphisms and multipliers of function spaces on groups, semigroups, etc.
Secondary: 22D15: Group algebras of locally compact groups 46L10: General theory of von Neumann algebras


Ozawa, Narutaka. Examples of groups which are not weakly amenable. Kyoto J. Math. 52 (2012), no. 2, 333--344. doi:10.1215/21562261-1550985.

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