Integration of differential forms on schemes.
Integration of differential forms on schemes.
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方案上微分形式的整合。
DOI:
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发表时间:
1990
期刊:
影响因子:
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通讯作者:
E. Kunz
中科院分区:
文献类型:
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作者:
R. Hübl;E. Kunz
In the last two decades numerous papers have been written about the algebraic theory of residues. In these treatments the theory has been developed with various methods and in various degrees of generality, and it has been applied to many problems in algebra and geometry (cf. [RD], [Ho], [Ke], [Kul], [Ll], [L2], [SS 2], [V]; for the complex analytic theory we refer to [GH], chap. V in the absolute case, resp. [B] in the relative Situation). In this paper we would like to introduce one more approach to the theory of residues. It is closely related to the concepts developed in [Kul] and [SS 2], however it is considerably more general than these theories. We are interested in separated morphisms / : X — » Υ of noetherian schemes, with / being equidimensional of dimension d and generically smooth. (The latter condition may be weakened, using the techniques of [KW]. For simplicity we will restrict ourselves to the above case, and we leave the easy but technical generalizations to the reader.) In the Situation described above the sheaf α)χ/γ of regul r differential forms of degree d of X/Y is defined ([KW], §3, §4). It is a subsheaf of ^χ(Ωχ/γ), the sheaf of meromorphic d-forms of X/Y (cf. [EGA] IV, (20. 1. 5)). We are interested in the Integration and the calculation of residues of regul r d-forms, or — to be precise — of their local cohomology classes with supports in suitable finite subschemes Z/Y of X/Y. In this paper we shall call "integral" what is often called "residue", and we shall reserve the word "residue" for a punctual formation at the closed points of X.