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arXiv · 0802.1652

Mirabolic affine Grassmannian and character sheaves

Michael Finkelberg·Victor Ginzburg·Roman Travkin
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Abstract

We compute the Frobenius trace functions of mirabolic character sheaves defined over a finite field. The answer is given in terms of the character values of general linear groups over the finite field, and the structure constants of multiplication in the mirabolic Hall-Littlewood basis of symmetric functions, introduced by Shoji.

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Michael Finkelberg, Victor Ginzburg, Roman Travkin. 2008-02-12. Mirabolic affine Grassmannian and character sheaves. https://doi.org/10.1007/s00029-009-0509-x

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