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Equivariant K-theory of affine flag manifolds and affine Grothendieck polynomials

Masaki Kashiwara·Mark Shimozono
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Abstract

We study the equivariant K-group of the affine flag manifold with respect to the Borel group action. We prove that the structure sheaf of the (infinite-dimensional) Schubert variety in the K-group is represented by a unique polynomial, which we call the affine Grothendieck polynomial.

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Masaki Kashiwara, Mark Shimozono. 2006-01-23. Equivariant K-theory of affine flag manifolds and affine Grothendieck polynomials. https://doi.org/10.1215/00127094-2009-032

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