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arXiv · 2610.01460

Free groups amenably act on unital simple AF-algebras

Yuhei Suzuki
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Abstract

We show that free groups admit amenable actions on unital simple AF-algebras. This settles, for free groups, the last remaining case of the existence problem for amenable actions of non-amenable groups on classifiable simple C*-algebras. The proof relies on the Baire category theorem. This result was obtained with substantial assistance from GPT-6 Astra.

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Yuhei Suzuki. 2026-10-01. Free groups amenably act on unital simple AF-algebras. https://arxiv.org/abs/2610.01460

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