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arXiv · 1012.0613

Examples of groups which are not weakly amenable

Narutaka Ozawa
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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.

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Narutaka Ozawa. 2010-12-03. Examples of groups which are not weakly amenable. https://doi.org/10.1215/21562261-1550985

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