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arXiv · 2505.18569

Strict comparison for twisted group C*-algebras

Sven Raum·Hannes Thiel·Eduard Vilalta
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Abstract

We prove that any reduced twisted group C*-algebra of a selfless group with the rapid decay property is selfless. As an application, we show that twisted group C*-algebras of acylindrically hyperbolic groups (possibly with nontrivial finite radical) and rapid decay are pure, and hence have strict comparison.

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Sven Raum, Hannes Thiel, Eduard Vilalta. 2025-05-24. Strict comparison for twisted group C*-algebras. https://arxiv.org/abs/2505.18569

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