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arXiv · 1803.05515

Sphericality and Smoothness of Schubert Varieties

Mahir Bilen Can·Reuven Hodges
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Abstract

We consider the action of the Levi subgroup of a parabolic subgroup that stabilizes a Schubert variety. We show that a smooth Schubert variety is a homogeneous space for a parabolic subgroup, or it has a smooth Schubert divisor. Further, we show that all smooth Schubert varieties in a (partial) flag variety of a rank two simple algebraic group are spherical.

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Mahir Bilen Can, Reuven Hodges. 2018-03-14. Sphericality and Smoothness of Schubert Varieties. https://arxiv.org/abs/1803.05515

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