Bounds on weights of nearby cycles and Wakimoto sheaves on affine flag manifolds
نویسندگان
چکیده
We study certain nearby cycles sheaves on an affine flag manifold which arise naturally in the Beilinson-Gaitsgory deformation of the affine flag manifold to the affine Grassmannian. We study the multiplicity functions we introduced in an earlier paper, which encode the data of the Jordan-Hoelder series. We prove the multiplicity functions are polynomials in q, and we give a sharp bound for their degrees. Our results apply as well to the nearby cycles in the p-adic deformation of Laumon-Haines-Ngô, and also to Wakimoto sheaves.
منابع مشابه
Fe b 20 05 Bounds on weights of nearby cycles and Wakimoto sheaves on affine flag manifolds
Let G be a split connected reductive group over a finite field Fp with algebraic closure k, fix an Iwahori subgroup B ⊂ G(Fp([[t]])) and let F l = G(k((t)))/Bk denote the affine flag variety of G. Let q denote a power of p and fix a prime l 6= p. In [GH], the authors study the Jordan-Hölder series for objects in the Hecke category P q (F l,Ql). This is the category of B-equivariant perverse Wei...
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