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arXiv · 2304.07457

Wreath-like products of groups and their von Neumann algebras II: Outer automorphisms

I. Chifan·A. Ioana·D. Osin·B. Sun
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Abstract

Given a countable group $G$, let ${\rm L}(G)$ denote its von Neumann algebra. For a wide class of ICC groups with Kazhdan's property (T), we confirm a conjecture of V.F.R. Jones asserting that $Out(\text{L}(G))\cong Char (G)\rtimes Out(G)$. As an application, we show that, for every countable group $Q$, there exists an ICC group $G$ with property (T) such that $Out(\text{L}(G))\cong Q$.

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I. Chifan, A. Ioana, D. Osin, B. Sun. 2023-04-15. Wreath-like products of groups and their von Neumann algebras II: Outer automorphisms. https://arxiv.org/abs/2304.07457

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