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arXiv · 2608.08150

Vanishing of $\ell^2$-Betti numbers for inner amenable groups

Robin Tucker-Drob
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Abstract

We prove that every countable inner amenable group has vanishing $\ell^2$-Betti numbers in all degrees. This was previously open in every degree $n\geq2$.

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Robin Tucker-Drob. 2026-08-08. Vanishing of $\ell^2$-Betti numbers for inner amenable groups. https://arxiv.org/abs/2608.08150

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