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arXiv · 1608.01153

Operator ultra-amenability

Brian E. Forrest·Volker Runde·Kyle Schlitt
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Abstract

Extending M.\ Daws' definition of ultra-amenable Banach algebras, we introduce the notion of operator ultra-amenability for completely contractive Banach algebras. For a locally compact group $G$, we show that the operator ultra-amenability of $A(G)$ imposes severe restrictions on $G$. In particular, it forces $G$ to be a discrete, amenable group with no infinite abelian subgroups. For various classes of such groups, this means that $G$ is finite.

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Brian E. Forrest, Volker Runde, Kyle Schlitt. 2016-08-03. Operator ultra-amenability. https://arxiv.org/abs/1608.01153

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