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Multiplicities of Singular Points in Schubert Varieties of Grassmannians

V. Kreiman·V. Lakshmibai
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Abstract

We give a closed-form formula for the Hilbert function of the tangent cone at the identity of a Schubert variety X in the Grassmannian in both group theoretic and combinatorial terms. We also give a formula for the multiplicity of X at the identity, and a Grobner basis for the ideal defining the intersection of X with the opposite cell as a closed subvariety of the opposite cell. We give conjectures for the Hilbert function and multiplicity at points other than the identity.

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V. Kreiman, V. Lakshmibai. 2001-08-09. Multiplicities of Singular Points in Schubert Varieties of Grassmannians. https://arxiv.org/abs/math/0108071

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