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arXiv · 2510.13309

Non-strong ergodicity of canonical actions of the Thompson groups

Ryoya Arimoto
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Abstract

We show that the canonical actions of the Thompson group V and its generalizations on the Cantor set are not strongly ergodic. This implies that the associated crossed product von Neumann algebras are not full. This also yields a non-embedding result for the Thompson groups.

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Ryoya Arimoto. 2025-10-15. Non-strong ergodicity of canonical actions of the Thompson groups. https://arxiv.org/abs/2510.13309

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