Ramification theory for varieties over a perfect field
نویسندگان
چکیده
If p2 : Γ → U is proper, Γ∗ = pr1∗ ◦ pr∗ 2 : H c (U,Q ) → H c (U,Q ) is defined. Write Tr(Γ∗ : H∗ c (UF̄ ,Q )) = ∑2d q=0(−1)Tr(Γ : H c (UF̄ ,Q )). Assume X: smooth U ⊂ X: the complement of a divisor D = D1 ∪ · · · ∪ Dm with simple normal crossings. Define p : (X ×X)′ → X ×X: the blow-up at D1 ×D1, . . . , Dm ×Dm ∆X = X → (X ×X)′: the log diagonal. Theorem 1.2 Let Γ̄′ be the closure of Γ in (X ×X)′ and assume Γ̄′ ∩ (D ×X)′ ⊂ Γ̄′ ∩ (X ×D)′ (1.2)
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تاریخ انتشار 2004