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arXiv · 1710.02392

The cup product of Brooks quasimorphisms

Michelle Bucher·Nicolas Monod
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Abstract

We prove the vanishing of the cup product of the bounded cohomology classes associated to any two Brooks quasimorphisms on the free group. This is a consequence of the vanishing of the square of a universal class for tree automorphism groups.

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Michelle Bucher, Nicolas Monod. 2017-10-06. The cup product of Brooks quasimorphisms. https://arxiv.org/abs/1710.02392

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