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arXiv · 2312.11154

Normality of Schubert varieties in affine Grassmannians

Patrick Bieker·Timo Richarz
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Abstract

We classify all normal Schubert varieties in the affine Grassmannian of a semisimple group over an arbitrary field with special attention to small positive characteristic. The proof is elementary and relies on tangent space calculations for quasi-minuscule Schubert varieties, a refined Levi lemma in positive characteristic and the classification of minimal degenerations.

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Patrick Bieker, Timo Richarz. 2023-12-18. Normality of Schubert varieties in affine Grassmannians. https://arxiv.org/abs/2312.11154

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