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arXiv · 0705.1420

Every compact group arises as the outer automorphism group of a II_1 factor

Sébastien Falguières·Stefaan Vaes
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Abstract

We show that any compact group can be realized as the outer automorphism group of a factor of type II_1. This has been proved in the abelian case by Ioana, Peterson and Popa applying Popa's deformation/rigidity techniques to amalgamated free product von Neumann algebras. Our methods are a generalization of theirs.

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Sébastien Falguières, Stefaan Vaes. 2008-02-07. Every compact group arises as the outer automorphism group of a II_1 factor. https://arxiv.org/abs/0705.1420

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