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Related papers: Exact couples in semiabelian categories revisited

200 papers

Holm (H. Holm, Modules with cosupport and injective functors, Algebr. Represent. Theor., 13 (2010), 543-560) considers categories of right modules dual to those with support in a set of finitely presented modules. We extend some of his…

Representation Theory · Mathematics 2013-04-17 Akeel Ramadan Mehdi , Mike Prest

Abelian categories provide a self-dual axiomatic context for establishing homomorphism theorems (such as the isomorphism theorems and homological diagram lemmas) for abelian groups, and more generally, modules. In this paper we describe a…

Category Theory · Mathematics 2020-06-23 Amartya Goswami , Zurab Janelidze

The purpose of this paper is to initiate a development of a new non-pointed counterpart of semi-abelian categorical algebra. We are making, however, only the first step in it by giving equivalent definitions of what we call ideally exact…

Category Theory · Mathematics 2023-08-21 George Janelidze

We develop the theory of exact completions of regular $\infty$-categories, and show that the $\infty$-categorical exact completion (resp. hypercompletion) of an abelian category recovers the connective half of its bounded (resp. unbounded)…

Category Theory · Mathematics 2023-10-20 Germán Stefanich

We establish a Galois-theoretic interpretation of cohomology in semi-abelian categories: cohomology with trivial coefficients classifies central extensions, also in arbitrarily high degrees. This allows us to obtain a duality, in a certain…

Category Theory · Mathematics 2015-11-24 Diana Rodelo , Tim Van der Linden

Necessary and sufficient conditions for the exactness (in the algebraic sense) of certain sequences of continuous group homomorphisms are established.

Functional Analysis · Mathematics 2025-06-23 Dinamérico P. Pombo

In this article, we compare the cohomology between the categories of modules of the diagram algebras and the categories of modules of its input algebras. Our main result establishes a sufficient condition for exact split pairs between these…

Representation Theory · Mathematics 2025-02-20 Sulakhana Chowdhury , Geetha Thangavelu

The paper establishes new relationship between cohomology, extensions and automorphisms of quandles. We derive a four term exact sequence relating quandle 1-cocycles, second quandle cohomology and certain group of automorphisms of an…

Geometric Topology · Mathematics 2021-07-27 Valeriy Bardakov , Mahender Singh

The relative Gromov seminorm is a finer invariant than stable commutator length where a relative homology class is fixed. We show a duality result between bounded cohomology and the relative Gromov seminorm, analogously to Bavard duality…

Geometric Topology · Mathematics 2024-08-16 Alexis Marchand

We consider a notion of exact sequences in any -not necessarily exact- pointed category relative to a given (E;M)-factorization structure. We apply this notion to introduce and investigate a new notion of exact sequences of semimodules over…

Category Theory · Mathematics 2011-11-03 Jawad Abuhlail

Let A and B be abelian categories with enough projective and injective objects, and T : A-B a left exact additive functor. Then one has a comma category (B*T). It is shown that If T : A-B is X-exact, then (*X, X) is a (hereditary) cotorsion…

Category Theory · Mathematics 2023-10-25 Yuan Yuan , Jian He , Dejun Wu

Recently, symmetric categorical groups are used for the study of the Brauer groups of symmetric monoidal categories. As a part of these efforts, some algebraic structures of the 2-category of symmetric categorical groups $\mathrm{SCG}$ are…

Category Theory · Mathematics 2008-11-18 Hiroyuki Nakaoka

This paper is based on the material of Section 4 and Appendix C in arXiv:1503.05523v6, which was excluded from the subsequent versions of arXiv:1503.05523. We present the definition of a dedualizing complex of bicomodules over a pair of…

Category Theory · Mathematics 2019-07-19 Leonid Positselski

Given a pair of number fields with isomorphic rings of adeles, we construct bijections between objects associated to the pair. For instance we construct an isomorphism of Brauer groups that commutes with restriction. We additionally…

Group Theory · Mathematics 2018-11-14 Benjamin Linowitz , D. B. McReynolds , Nicholas Miller

The notion of a duality between two derived functors as well as an extension theorem for derived functors to larger categories in which they need not be defined is introduced. These ideas are then applied to extend and study the coext…

Rings and Algebras · Mathematics 2014-02-19 Anastasis Kratsios

In the previous article "Hearts of twin cotorsion pairs on exact categories", we introduced the notion of the heart for any cotorsion pair on an exact category with enough projectives and injectives, and showed that it is an abelian…

Representation Theory · Mathematics 2020-03-16 Yu Liu

An equivalent description of a symmetric monoidal category is introduced in which, instead of separate associator and commutator isomorphisms satisfying the usual coherence axioms, we simply have associo-commutator isomorphisms satisfying…

Category Theory · Mathematics 2025-12-25 Josep Elgueta

We survey the basics of homological algebra in exact categories in the sense of Quillen. All diagram lemmas are proved directly from the axioms, notably the five lemma, the 3 x 3-lemma and the snake lemma. We briefly discuss exact functors,…

History and Overview · Mathematics 2009-04-22 Theo Buehler

Given a right exact functor from an abelian category into another abelian category, there is an associated abelian category called the comma category of the functor. In this paper, we characterize when left Frobenius pairs (resp. strong…

Rings and Algebras · Mathematics 2023-10-23 Yajun Ma , Dandan Sun , Rongmin Zhu , Jiangsheng Hu

In this work we discuss an elementary self-contained presentation of the notion of a semiabelian category, introduced by Raikov and Palamodov. Fundamental examples of (non-abelian) semiabelian categories occuring in Functional Analysis and…

Functional Analysis · Mathematics 2015-03-11 Dinamérico P. Pombo