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arXiv · 2507.04549

Automorphism group of flag varieties with non-reduced stabilizer

Matilde Maccan
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Abstract

We consider rational projective homogeneous varieties over an algebraically closed field of positive characteristic, namely quotients of a semi-simple group by a possibly non-reduced parabolic subgroup. We determine the group scheme structure of the neutral component of their automorphism group, generalizing the classical result of Demazure on automorphism groups of flag varieties.

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Matilde Maccan. 2025-07-06. Automorphism group of flag varieties with non-reduced stabilizer. https://arxiv.org/abs/2507.04549

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