Bounded cohomology of transformation groups

Michael Brandenbursky; Michal Marcinkowski

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arXiv · 1902.11067

Bounded cohomology of transformation groups

Michael Brandenbursky·Michal Marcinkowski

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Abstract

Let $M$ be a complete connected Riemannian manifold of finite volume. In this paper we present a new method of constructing classes in bounded cohomology of transformation groups such as $Homeo_0(M,\mu)$, $Diff_0(M,vol)$ and $Symp_0(M,\omega)$ (in case $M$ is symplectic). As an application we show that, under certain conditions on $\pi_1(M)$, the $3^{rd}$ bounded cohomology of these groups is infinite dimensional.

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Michael Brandenbursky, Michal Marcinkowski. 2019-02-28. Bounded cohomology of transformation groups. https://arxiv.org/abs/1902.11067

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