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arXiv · 2402.04449

Factoriality of groupoid von Neumann algebras

Tey Berendschot·Soham Chakraborty·Milan Donvil·Se-Jin Kim
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Abstract

We give a characterisation of factoriality of the groupoid von Neumann algebra $L(\mathcal{G})$ associated to a discrete measured groupoid $(\mathcal{G},\mu)$. We introduce the notion of groupoids with `infinite conjugacy classes' and show that this property together with ergodicity of the groupoid is equivalent to factoriality of $L(\mathcal{G})$.

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Tey Berendschot, Soham Chakraborty, Milan Donvil, Se-Jin Kim. 2024-02-06. Factoriality of groupoid von Neumann algebras. https://arxiv.org/abs/2402.04449

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