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arXiv · 2610.05986

Computable presentations of reduced group C*-algebras of hyperbolic groups

Isaac Goldbring
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Abstract

Answering a question of Thomas Sinclair, we show that the standard presentation of the reduced group C*-algebra $C^*_r(G)$ of an infinite hyperbolic group $G$ is computable. The main ingredient in proving this result is showing that the Gromov boundary $\partial G$ of $G$ admits a computably compact metric presentation for which the natural action of $G$ on $\partial G$ is computable.

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Isaac Goldbring. 2026-10-05. Computable presentations of reduced group C*-algebras of hyperbolic groups. https://arxiv.org/abs/2610.05986

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