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arXiv · 2111.15245

Isotropic Kempf--Laksov flag bundles

Lionel Darondeau
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Abstract

We introduce analogs of the Kempf--Laksov desingularizations of Schubert bundles in (non-necessary Lagrangian) symplectic Grassmann bundles. In this setting, these are (possibly singular) irreducible flag bundles that are birational to Schubert bundles, and can be described as chains of zero-loci of regular sections in projectivized bundles. The orthogonal analogs are also presented. We immediatly derive universal Gysin formulas for isotropic Schubert bundles from these very constructions.

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Lionel Darondeau. 2021-11-30. Isotropic Kempf--Laksov flag bundles. https://arxiv.org/abs/2111.15245

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