Factoriality of twisted locally compact group von Neumann algebras

2024/12/20 by Stefaan Vaes, Vaes, Stefaan · 4 citations
Mathematics · #Advanced Operator Algebra Research #Advanced Topics in Algebra #FOS: Mathematics #Group Theory (math.GR) #Operator Algebras (math.OA) #Spectral Theory in Mathematical Physics

paper · pdf · doi:10.48550/arxiv.2412.15733

openalex publication_date 2024/12/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

In this short note, we construct an exotic example of a locally compact group G with a Borel 2-cocycle ω such that the non-twisted group von Neumann algebra L(G) is a factor, while the twisted group von Neumann algebra L_ω(G) has a diffuse center.

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