PBW-degenerated Demazure modules and Schubert varieties for triangular elements

@article{Fourier2016PBWdegeneratedDM,
  title={PBW-degenerated Demazure modules and Schubert varieties for triangular elements},
  author={Ghislain Fourier},
  journal={J. Comb. Theory, Ser. A},
  year={2016},
  volume={139},
  pages={132-152}
}
  • G. Fourier
  • Published 2016
  • Mathematics, Computer Science
  • J. Comb. Theory, Ser. A
We study certain faces of the normal polytope introduced by Feigin, Littelmann and the author whose lattice points parametrize a monomial basis of the PBW-degenerated of simple modules for sl n + 1 . We show that lattice points in these faces parametrize monomial bases of PBW-degenerated Demazure modules associated to Weyl group elements satisfying a certain closure property, for example Kempf elements.These faces are again normal polytopes and their Minkowski sum is compatible with tensor… Expand

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