Vanishing of cohomology over Cohen–Macaulay 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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Article history: Received 26 April 2007 Communicated by Michel Van Den Bergh
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ژورنال
عنوان ژورنال: Manuscripta Mathematica
سال: 2012
ISSN: 0025-2611,1432-1785
DOI: 10.1007/s00229-012-0540-7