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arXiv · 1708.01763

A von Neumann algebra characterization of property (T) for groupoids

Martino Lupini
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Abstract

For an arbitrary discrete probability-measure-preserving groupoid $G$, we provide a characterization of property (T) for $G$ in terms of the groupoid von Neumann algebra $L(G)$. More generally, we obtain a characterization of relative property (T) for a subgroupoid $H\subset G$ in terms of the inclusion $L\left( H\right) \subset L\left( G\right) $.

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Martino Lupini. 2017-08-05. A von Neumann algebra characterization of property (T) for groupoids. https://doi.org/10.1017/s144678871800040x

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