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arXiv · 1407.7450

L2-invisibility of symmetric operad groups

Werner Thumann
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Abstract

We show a homological result for the class of planar or symmetric operad groups: We show that under certain conditions, group (co)homology of such groups with certain coefficients vanishes in all dimensions, provided it vanishes in dimension $0$. This can be applied for example to $l^2$-homology or cohomology with coefficients in the group ring. As a corollary, we obtain explicit vanishing results for Thompson-like groups such as the Brin-Thompson groups $nV$.

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Werner Thumann. 2016-04-02. L2-invisibility of symmetric operad groups. https://doi.org/10.2140/agt.2016.16.2229

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