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arXiv · 2412.15463

Bounded cohomology of groups acting on trees with almost prescribed local actions

Giuseppe Bargagnati·Elena Bogliolo
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Abstract

We prove the vanishing of bounded cohomology of the groups acting on trees with almost prescribed local actions $G(F, F')$, where $F<F'$ are finite permutation groups such that $F'$ is 2-transitive. By contrast, when $F'$ is not 2-transitive, we prove that the second bounded cohomology with real coefficients of the groups $G(F, F')$ is infinite dimensional.

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Giuseppe Bargagnati, Elena Bogliolo. 2024-12-19. Bounded cohomology of groups acting on trees with almost prescribed local actions. https://arxiv.org/abs/2412.15463

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