Amenability for unitary groups of simple monotracial C*-algebras

Narutaka Ozawa

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arXiv · 2307.08267

Amenability for unitary groups of simple monotracial C*-algebras

Narutaka Ozawa

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Abstract

We prove the following two results. First, the isometry semigroup of a unital properly infinite nuclear C*-algebra is right amenable. Second, the unitary group of a unital simple monotracial C*-algebra whose tracial GNS representation is hyperfinite is skew-amenable in the weak topology. This answers in part a conjecture of Alekseev, Schmidt, and Thom and a question of Pestov.

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Narutaka Ozawa. 2023-07-17. Amenability for unitary groups of simple monotracial C*-algebras. https://arxiv.org/abs/2307.08267

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