Abelian Subcategories Closed under Extensions: K-theory and Decompositions
نویسنده
چکیده
In this paper we study wide subcategories. A full subcategory of R-modules is said to be wide if it is abelian and closed under extensions. Hovey [Hov01] gave a classification of wide subcategories of finitely presented modules over regular coherent rings in terms of certain specialisation closed subsets of Spec(R). We use this classification theorem to study K-theory and “Krull-Schmidt” decompositions for wide subcategories of modules.
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