Crossed-products by locally compact groups: Intermediate subfactors

Rémi Boutonnet; Arnaud Brothier

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arXiv · 1611.10121

Crossed-products by locally compact groups: Intermediate subfactors

Rémi Boutonnet·Arnaud Brothier

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Abstract

We study actions of locally compact groups on von Neumann factors and the associated crossed-product von Neumann algebras. In the setting of totally disconnected groups we provide sufficient conditions on an action $G\curvearrowright Q$ ensuring that the inclusion $Q \subset Q \rtimes G$ is irreducible and that every intermediate subfactor is of the form $Q \rtimes H$ for a closed subgroup $H<G$. This partially generalizes a result of Izumi-Longo-Popa [ILP98] and Choda [Ch78]. We moreover show that one can not hope to use their strategy for non-discrete groups.

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BibTeX RIS

Rémi Boutonnet, Arnaud Brothier. 2016-12-02. Crossed-products by locally compact groups: Intermediate subfactors. https://arxiv.org/abs/1611.10121

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