We prove the following results for the subcategories of an abelian category: 1) The full
subcategory whose objects are kernels of the maps between two covariantly finite …

Introduction. The study of homologically finite subcategories has turned out to be important
in several contexts, especially in the representation theory of artin algebras. In this paper we …

For an arbitrary ring R (always associative with 1) we denote by Mod R th category of all left
R-modules and by mod R the full subcategory of Mod R wi objects the finitely presented …

Contravariantly finite resolving subcategories of the category of finitely generated modules
have been playing an important role in the representation theory of algebras. In this paper …

Let Mod-S denote the category of S-modules, where S is a small pre-additive category.
Using the notion of relative derived categories of functor categories, we generalize Rickard's …

Mod ª Ex C, Ab, M¬ Hom y, M my Ž. Ž. Ž. is an equivalence. Thus we can replace a-module
by an exact functor Ž. op C ª Ab. Of course, since the work of Auslander, it has been common …

The use of category equivalences for the study of endomorphism rings stems from the Morita
theorem. In a sense, this theorem can be viewed as stating that if P is a finitely generated …

In the context of semi-abelian categories, we develop some new xaspects of the categorical
theory of central extensions by Janelidze and Kelly. If C is a semi-abelian category and X is …

In a series of papers additive subbifunctors $ F $ of the bifunctor $\operatorname {Ext} _
{\Lambda}(,) $ are studied in order to establish a relative homology theory for an artin …

In the representation theory of algebras situations occur where one has to transport an exact
structure E on a category A to a factor category by a relation R. We characterize when this is …