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arXiv · 2204.04480

Every countable group admits amenable actions on stably finite simple C*-algebras

Yuhei Suzuki
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Abstract

We give the first examples of (non-amenable group) amenable actions on stably finite simple C*-algebras. More precisely, we give such actions for any countable group in an explicit way. The main ingredients of our construction are the full Fock space of the regular representation and a trace-scaling automorphism.

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Yuhei Suzuki. 2023-07-17. Every countable group admits amenable actions on stably finite simple C*-algebras. https://doi.org/10.1353/ajm.2026.a980768

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