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arXiv · 1311.2071

Geometric constant term functor(s)

V. Drinfeld·D. Gaitsgory
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Abstract

We study the Eisenstein series and constant term functors in the framework of geometric theory of automorphic functions. Our main result says that for a parabolic P in G with Levi quotient M, the !-constant term functor CT_!:D-mod(Bun_G)-> D-mod(Bun_M) is canonically isomorphic to the *-constant term functor CT^-_*:D-mod(Bun_G)\to D-mod(Bun_M), taken with respect to the opposite parabolic P^-.

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V. Drinfeld, D. Gaitsgory. 2013-11-08. Geometric constant term functor(s). https://arxiv.org/abs/1311.2071

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