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arXiv · 2501.09496

Cohomology of type $B$ real permutohedral varieties

Younghan Yoon
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Abstract

Type $A$ and type $B$ permutohedral varieties are classic examples of mathematics, and their topological invariants are well known. This naturally leads to the investigation of the topology of their real loci, known as type $A$ and type $B$ real permutohedral varieties. The rational cohomology rings of type $A$ real permutohedral varieties are fully described in terms of alternating permutations. Until now, only rational Betti numbers of type $B$ real permutohedral varieties have been described in terms of $B$-snakes. In this paper, we explicitly describe the multiplicative structure of the cohomology rings of type $B$ real permutohedral varieties in terms of $B$-snakes.

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Younghan Yoon. 2025-05-26. Cohomology of type $B$ real permutohedral varieties. https://doi.org/10.1112/blms.70125

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