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Résolutions de Demazure affines et formule de Casselman-Shalika géométrique

B. C. Ngo·P. Polo
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Abstract

We prove a conjecture of Frenkel, Gaitsgory, Kazhdan and Vilonen, related to Fourier coefficients of spherical perverse sheaves on the affine Grassmannian associated to a a split reductive group. Our proof is an extension of the proof given by the first author in the case of GL(n) (see math/9801109); it relies on the study of certain resolutions of Schubert varieties in the affine Grassmannian, built from the so-called minuscule or quasi-minuscule cases.

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B. C. Ngo, P. Polo. 2000-05-02. Résolutions de Demazure affines et formule de Casselman-Shalika géométrique. https://arxiv.org/abs/math/0005022

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