VANISHING OF COHOMOLOGY OVER COMPLETE INTERSECTION RINGS
نویسندگان
چکیده
منابع مشابه
Vanishing of Cohomology over Gorenstein Rings of Small Codimension
We prove that if M , N are finite modules over a Gorenstein local ring R of codimension at most 4, then the vanishing of Ext R (M,N) for n ≫ 0 is equivalent to the vanishing of Ext R (N,M) for n ≫ 0. Furthermore, if b R has no embedded deformation, then such vanishing occurs if and only if M or N has finite projective dimension.
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متن کاملLocal Cohomology with Respect to a Cohomologically Complete Intersection Pair of Ideals
Let $(R,fm,k)$ be a local Gorenstein ring of dimension $n$. Let $H_{I,J}^i(R)$ be the local cohomology with respect to a pair of ideals $I,J$ and $c$ be the $inf{i|H_{I,J}^i(R)neq0}$. A pair of ideals $I, J$ is called cohomologically complete intersection if $H_{I,J}^i(R)=0$ for all $ineq c$. It is shown that, when $H_{I,J}^i(R)=0$ for all $ineq c$, (i) a minimal injective resolution of $H_{I,...
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ژورنال
عنوان ژورنال: Glasgow Mathematical Journal
سال: 2014
ISSN: 0017-0895,1469-509X
DOI: 10.1017/s0017089514000408