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arXiv · 1206.4793

Weak notions of normality and vanishing up to rank in L2-cohomology

Uri Bader·Alex Furman·Roman Sauer
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Abstract

We study vanishing results for L2-cohomology of countable groups under the presence of subgroups that satisfy some weak normality condition. As a consequence we show that the L2-Betti numbers of SL(n,R) for any infinite integral domain R vanish below degree n-1. We also give a uniform proof for the vanishing of L2-Betti numbers of Thompson's groups F and T.

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Uri Bader, Alex Furman, Roman Sauer. 2013-02-10. Weak notions of normality and vanishing up to rank in L2-cohomology. https://arxiv.org/abs/1206.4793

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