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arXiv · 2402.19461

Wreath-like products of groups and their von Neumann algebras III: Embeddings

Ionut Chifan·Adrian Ioana·Denis Osin·Bin Sun
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Abstract

For a class of wreath-like product groups with property (T), we describe explicitly all the embeddings between their von Neumann algebras. This allows us to provide a continuum of ICC groups with property (T) whose von Neumann algebras are pairwise non (stably) embeddable. We also give a construction of groups in this class only having inner injective homomorphisms. As an application, we obtain examples of group von Neumann algebras which admit only inner endomorphisms.

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Ionut Chifan, Adrian Ioana, Denis Osin, Bin Sun. 2024-02-29. Wreath-like products of groups and their von Neumann algebras III: Embeddings. https://arxiv.org/abs/2402.19461

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