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Duality for Cousin Complexes

Pramathanath Sastry

math.AGarXiv:math/0401166

Abstract

We relate the variance theory for Cousin complexes -# developed by Lipman, Nayak and the author to Grothendieck duality for Cousin complexes. Specifically for a Cousin complex F on (Y, Δ)--with Δa codimension function on a formal scheme Y (noetherian, universally catenary)--and a pseudo-finite type map f:(X,Δ') --> (Y,Δ) of such pairs of schemes with codimension functions, we show there is a derived category map γ!f(F):f#F --> f!F, which is functorial as F varies over Cousin complexes on (Y,Δ), and induces an isomorphism f#F = E(f#F) --> E(f!F). E here is the Cousin functor for the codimension function Δ. Further, we give conditions under which γ!f is an isomorphism. We also generalize the Residue Theorem of Grothendieck for residual complexes to Cousin complexes by defining trace as a sum of local residues when the map f is pseudo-proper.

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