Classification of actions of compact abelian groups on subfactors with index less than 4

Koichi Shimada

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arXiv · 1412.4319

Classification of actions of compact abelian groups on subfactors with index less than 4

Koichi Shimada

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Abstract

We calssify actions of discrete abelian groups on some inclusions of von Neumann algebras, up to cocycle conjugacy. As an application, we classify actions of compact abelian groups on the inclusions of AFD factors of type II_1 with index less than 4, up to stable conjugacy.

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Koichi Shimada. 2014-12-14. Classification of actions of compact abelian groups on subfactors with index less than 4. https://arxiv.org/abs/1412.4319

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