Degenerations of graded Cohen-Macaulay modules
نویسندگان
چکیده
منابع مشابه
On the Cohen-macaulay Modules of Graded Subrings
We give several characterizations for the linearity property for a maximal Cohen-Macaulay module over a local or graded ring, as well as proofs of existence in some new cases. In particular, we prove that the existence of such modules is preserved when taking Segre products, as well as when passing to Veronese subrings in low dimensions. The former result even yields new results on the existenc...
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Let I ⊂ R be a graded ideal in the polynomial ring R = K[x1, . . . , xn] where K is a field, and fix a term order <. It has been shown in [17] that the Hilbert functions of the local cohomology modules of R/I are bounded by those of R/ in(I), where in(I) denotes the initial ideal of I with respect to <. In this note we study the question when the local cohomology modules of R/I and R/ in(I) hav...
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ژورنال
عنوان ژورنال: Journal of Commutative Algebra
سال: 2015
ISSN: 1939-2346
DOI: 10.1216/jca-2015-7-2-221