l2-Betti numbers of discrete and non-discrete groups

2015/09/17 by Roman Sauer, Sauer, Roman
Mathematics · #Advanced Operator Algebra Research #Algebraic Topology (math.AT) #FOS: Mathematics #Geometric and Algebraic Topology #Group Theory (math.GR) #Homotopy and Cohomology in Algebraic Topology

paper · pdf · doi:10.48550/arxiv.1509.05234

openalex publication_date 2015/09/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

This survey is an extended version of a talk during the Arbeitsgemeinschaft on totally disconnected locally compact groups, held in Oberwolfach in October 2014. We explain the definition of l2-Betti numbers of locally compact groups -- both discrete and non-discrete. Specific topics include proportionality principle, dimension function, Petersen's definition for locally compact groups, examples.

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