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arXiv · 2202.07323

Classification results for nonsingular Bernoulli crossed products

Stefaan Vaes·Bram Verjans
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Abstract

We prove rigidity and classification results for type III factors given by nonsingular Bernoulli actions of the free groups and more general free product groups. This includes a large family of nonisomorphic Bernoulli crossed products of type III$_1$ that cannot be distinguished by Connes $\tau$-invariant. These are the first such classification results beyond the well studied probability measure preserving case.

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Stefaan Vaes, Bram Verjans. 2022-02-15. Classification results for nonsingular Bernoulli crossed products. https://doi.org/10.4064/sm220217-11-5

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