Fe b 20 05 Bounds on weights of nearby cycles and Wakimoto sheaves on affine flag manifolds
نویسنده
چکیده
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 Weil-sheaves F on F l having the property that for any x ∈ F l(Fq), the trace of the Frobenius Frq on the stalk Fx satisfies Tr(Frq,Fx) ∈ Z[q, q ].
منابع مشابه
Bounds on weights of nearby cycles and Wakimoto sheaves on affine flag manifolds
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