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arXiv · 1504.04415

Free resolutions of some Schubert singularities

Manoj Kummini·V. Lakshmibai·Pramathanath Sastry·C. S. Seshadri
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Abstract

In this paper we construct free resolutions of certain class of closed subvarieties of affine spaces (the so-called "opposite big cells" of Grassmannians). Our class covers the determinantal varieties, whose resolutions were first constructed by A. Lascoux (Adv. Math., 1978). Our approach uses the geometry of Schubert varieties. An interesting aspect of our work is its connection to the computation of the cohomology of homogeneous bundles (that are not necessarily completely reducible) on partial flag varieties.

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Manoj Kummini, V. Lakshmibai, Pramathanath Sastry, C. S. Seshadri. 2015-04-17. Free resolutions of some Schubert singularities. https://arxiv.org/abs/1504.04415

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