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arXiv · 1307.7236

Spherical multiple flags

Piotr Achinger·Nicolas Perrin
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Abstract

For a reductive group G, the products of projective rational varieties homogeneous under G that are spherical for G have been classified by Stembridge. We consider the B-orbit closures in these spherical varieties and prove that under some mild restrictions they are normal, Cohen-Macaulay and have a rational resolution.

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Piotr Achinger, Nicolas Perrin. 2013-07-27. Spherical multiple flags. https://arxiv.org/abs/1307.7236

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