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arXiv · 2610.03309

Betti Numbers of Odd Biisotropic Symplectic Grassmannians

Anton Fonarev·Alexander Kuznetsov
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Abstract

We compute the singular cohomology groups of odd biisotropic symplectic Grassmannians $\operatorname{S_2Gr}(k, 2n+1)$ by presenting an explicit dimension-preserving combinatorial bijection between the Bialynicki-Birula cells in $\operatorname{S_2Gr}(k, 2n+1)$ and the Schubert cells in $\operatorname{Gr}(k, 2n+2-k)$.

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Anton Fonarev, Alexander Kuznetsov. 2026-10-02. Betti Numbers of Odd Biisotropic Symplectic Grassmannians. https://arxiv.org/abs/2610.03309

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