A certain Abelian category of weakly cofinite modules

Abstract

Let $R$ be a commutative Noetherian ring, $I$ an ideal of $R$ and $M$ an arbitrary $R$-module. We show that if the set $X=\cup_{i\geq 2}{\rm Supp}_R({\rm H}^{i}_{I}(R))$ is finite, then the category of all weakly cofinite modules with respect to the ideal $I$ of $R$ is an Abelian subcategory of the category of $R$-modules. In particular, it is true whenever ${\rm q}(I,R)\leq 1$.

Keywords

• Abelian category
• local cohomology
• weakly cofinite module
• weakly Laskerian module

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