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arXiv · 1605.04953

Demazure character formula for semi-infinite flag varieties

Syu Kato
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Abstract

We provide a proof that every Schubert variety of a semi-infinite flag variety is projectively normal. This gives us an interpretation of a Demazure module of a global Weyl module of a current Lie algebra as the (dual) space of the space of global sections of a semi-infinite Schubert variety. Moreover, we give geometric realizations of Feigin-Makedonskyi's generalized Weyl modules, and the $t = \infty$ specialization of non-symmetric Macdonald polynomials.

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Syu Kato. 2016-05-16. Demazure character formula for semi-infinite flag varieties. https://doi.org/10.1007/s00208-018-1652-5

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