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arXiv · 2208.03168

A refinement of bounded cohomology

Światosław R. Gal·Jarek Kędra
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Abstract

We introduce a refinement of bounded cohomology and prove that the suitable comparison homomorphisms vanish for an amenable group. We investigate in this context Thompson's group F and provide further evidence towards its amenability. We provide a source of nontrivial 1-bounded classes and show that the space of 1-bounded classes in degree 2 is huge.

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Światosław R. Gal, Jarek Kędra. 2022-08-05. A refinement of bounded cohomology. https://arxiv.org/abs/2208.03168

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