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arXiv · 1408.6414

Classification of type III Bernoulli crossed products

Stefaan Vaes·Peter Verraedt
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Abstract

Crossed products with noncommutative Bernoulli actions were introduced by Connes as the first examples of full factors of type III. This article provides a complete classification of the factors $(P,ϕ)^{\mathbb{F}_n} \rtimes \mathbb{F}_n$, where $\mathbb{F}_n$ is the free group and P is an amenable factor with an almost periodic state $ϕ$. We show that these factors are completely classified by the rank n of the free group $\mathbb{F}_n$ and Connes's Sd-invariant. We prove similar results for free product groups, as well as for classes of generalized Bernoulli actions.

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Stefaan Vaes, Peter Verraedt. 2015-05-05. Classification of type III Bernoulli crossed products. https://doi.org/10.1016/j.aim.2015.05.004

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