English

Examples of groups which are not weakly amenable

Operator Algebras 2015-01-14 v2 Functional Analysis Group Theory

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.

Keywords

Cite

@article{arxiv.1012.0613,
  title  = {Examples of groups which are not weakly amenable},
  author = {Narutaka Ozawa},
  journal= {arXiv preprint arXiv:1012.0613},
  year   = {2015}
}

Comments

10 pages; some remarks are clarified (v2)

R2 v1 2026-06-21T16:52:48.639Z