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arXiv · alg-geom/9709035

An algebraic cell decomposition of the nonnegative part of a flag variety

K. Rietsch
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Abstract

We study the nonnegative part B_{\ge 0} of the flag variety of a reductive algebraic group G, as defined by Lusztig. Using positivity properties of the canonical basis it is shown that B_{\ge 0} has an algebraic cell decomposition indexed by pairs w\le w' of the Weyl group. This result was conjectired by Lusztig in [Lu; Progress in Math 123].

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K. Rietsch. 1997-09-30. An algebraic cell decomposition of the nonnegative part of a flag variety. https://arxiv.org/abs/alg-geom/9709035

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