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Singularities of Affine Schubert Varieties
Symmetry, integrability and geometry: methods and applications, Tome 5 (2009) Cet article a éte moissonné depuis la source Math-Net.Ru

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This paper studies the singularities of affine Schubert varieties in the affine Grassmannian (of type $\mathrm A^{(1)}_\ell$). For two classes of affine Schubert varieties, we determine the singular loci; and for one class, we also determine explicitly the tangent spaces at singular points. For a general affine Schubert variety, we give partial results on the singular locus.
Keywords: Schubert varieties; affine Grassmannian; loop Grassmannian. 
@article{SIGMA_2009_5_a47,
     author = {Jochen Kuttler and Venkatramani Lakshmibai},
     title = {Singularities of {Affine} {Schubert} {Varieties}},
     journal = {Symmetry, integrability and geometry: methods and applications},
     year = {2009},
     volume = {5},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SIGMA_2009_5_a47/}
}
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Jochen Kuttler; Venkatramani Lakshmibai. Singularities of Affine Schubert Varieties. Symmetry, integrability and geometry: methods and applications, Tome 5 (2009). http://geodesic.mathdoc.fr/item/SIGMA_2009_5_a47/

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