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arXiv · 1910.14524

On invertible elements in reduced $C^*$-algebras of acylindrically hyperbolic groups

M. Gerasimova·D. Osin
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Abstract

Let $G$ be an acylindrically hyperbolic group. We prove that if $G$ has no non-trivial finite normal subgroups, then the set of invertible elements is dense in the reduced $C^\ast$-algebra of $G$. The same result is obtained for finite direct products of acylindrically hyperbolic groups.

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M. Gerasimova, D. Osin. 2019-10-31. On invertible elements in reduced $C^*$-algebras of acylindrically hyperbolic groups. https://arxiv.org/abs/1910.14524

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