DEGENERATE SCHUBERT VARIETIES IN TYPE A

@article{Chirivi2018DEGENERATESV,
  title={DEGENERATE SCHUBERT VARIETIES IN TYPE A},
  author={Rocco Chirivi' and Xin Gui Fang and Ghislain Fourier},
  journal={arXiv: Representation Theory},
  year={2018}
}
We introduce rectangular elements in the symmetric group. In the framework of PBW degenerations, we show that in type A the degenerate Schubert variety associated to a rectangular element is indeed a Schubert variety in a partial flag variety of the same type with larger rank. Moreover, the degenerate Demazure module associated to a rectangular element is isomorphic to the Demazure module for this particular Schubert variety of larger rank. This generalizes previous results by Cerulli Irelli… Expand
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