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arXiv · 2506.24029

The regular representation of Neretin groups is factorial

Basile Morando
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Abstract

We show that the left regular representation of Neretin groups is factorial, providing the first example of a non-discrete simple group with this property. This is based on a new criterion of factoriality for totally disconnected groups. For groups G satisfying the criterion, we determine the type of the factor L(G) and derive factoriality results for crossed products associated to G-actions on von Neumann algebras.

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Basile Morando. 2025-06-30. The regular representation of Neretin groups is factorial. https://arxiv.org/abs/2506.24029

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