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arXiv · 1612.04559

$L^2$-Betti numbers of totally disconnected groups and their approximation by Betti numbers of lattices

Henrik Densing Petersen·Roman Sauer·Andreas Thom
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Abstract

The main result is a general approximation theorem for normalised Betti numbers for Farber sequences of lattices in totally disconnected groups. Further, we contribute some computations and complements to the general theory of $L^2$-Betti numbers of totally disconnected groups.

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Henrik Densing Petersen, Roman Sauer, Andreas Thom. 2016-12-14. $L^2$-Betti numbers of totally disconnected groups and their approximation by Betti numbers of lattices. https://doi.org/10.1112/topo.12056

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