Graded Cohen-macaulayness for Commutative Rings Graded by Arbitrary Abelian Groups
نویسنده
چکیده
We consider a commutative ring R graded by an arbitrary abelian group G, and define the grade of a G-homogeneous ideal I on R in terms of vanishing of C̆ech cohomology. By defining the dimension in terms of chains of homogeneous prime ideals and supposing R satisfies a.c.c. on G-homogeneous ideals and has a unique G-homogeneous maximal ideal, we can define graded versions of the depth of R and Cohen-Macaulayness. Using these and the basic theory developed, we prove of a generalization of the fact that a Noetherian Zd-graded ring is (graded) Cohen-Macaulay if and only if it is Cohen-Macaulay under the trivial grading.
منابع مشابه
Results on Generalization of Burch’s Inequality and the Depth of Rees Algebra and Associated Graded Rings of an Ideal with Respect to a Cohen-Macaulay Module
Let be a local Cohen-Macaulay ring with infinite residue field, an Cohen - Macaulay module and an ideal of Consider and , respectively, the Rees Algebra and associated graded ring of , and denote by the analytic spread of Burch’s inequality says that and equality holds if is Cohen-Macaulay. Thus, in that case one can compute the depth of associated graded ring of as In this paper we ...
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