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arXiv · 2012.13368

The first $\ell^2$-Betti number and groups acting on trees

Indira Chatterji·Sam Hughes·Peter Kropholler
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Abstract

We generalise results of Thomas, Allcock, Thom-Petersen, and Kar-Niblo to the first $\ell^2$-Betti number of quotients of certain groups acting on trees by subgroups with free actions on the edge sets of the graphs.

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Indira Chatterji, Sam Hughes, Peter Kropholler. 2020-12-24. The first $\ell^2$-Betti number and groups acting on trees. https://doi.org/10.1017/s0013091521000663

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