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arXiv · 0908.4354

On the B-canonical splittings of flag varieties

Chuck Hague
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Abstract

Let G be a semisimple algebraic group over an algebraically closed field of positive characteristic. In this note, we show that an irreducible closed subvariety of the flag variety of G is compatibly split by the unique canonical Frobenius splitting if and only if it is a Richardson variety, i.e. an intersection of a Schubert and an opposite Schubert variety.

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Chuck Hague. 2010-05-25. On the B-canonical splittings of flag varieties. https://arxiv.org/abs/0908.4354

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