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arXiv · 2204.08344

Pointwise inner automorphisms of almost periodic factors

Cyril Houdayer·Yusuke Isono
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Abstract

We prove that a large class of nonamenable almost periodic type ${\rm III_1}$ factors $M$, including all McDuff factors that tensorially absorb $R_\infty$ and all free Araki-Woods factors, satisfy Haagerup-Stormer's conjecture (1988): any pointwise inner automorphism of $M$ is the composition of an inner and a modular automorphism.

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Cyril Houdayer, Yusuke Isono. 2022-04-18. Pointwise inner automorphisms of almost periodic factors. https://doi.org/10.1007/s00029-024-00949-z

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