Cohomology of quasi-abelianized braid groups

Filippo Callegaro; Ivan Marin

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arXiv · 2111.05731

Cohomology of quasi-abelianized braid groups

Filippo Callegaro·Ivan Marin

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Abstract

We investigate the rational cohomology of the quotient of (generalized) braid groups by the commutator subgroup of the pure braid groups. We provide a combinatorial description of it using isomorphism classes of certain families of graphs. We establish Poincar\'e dualities for them and prove a stabilization property for the infinite series of reflection groups.

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Filippo Callegaro, Ivan Marin. 2021-11-10. Cohomology of quasi-abelianized braid groups. https://arxiv.org/abs/2111.05731

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