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Related papers: Almost dual pairs and definable classes of modules

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This is the first in a series of papers that deals with duality statements such as Mukai-duality (T-duality, from algebraic geometry) and the Baum-Connes conjecture (from operator $K$-theory). These dualities are expressed in terms of…

Quantum Algebra · Mathematics 2009-07-27 Jonathan Block

We revisit a construction of wide subcategories going back to work of Ingalls and Thomas. To a torsion pair in the category $ R\operatorname{-}\operatorname{mod}$ of finitely presented modules over a left artinian ring $R$, we assign two…

Representation Theory · Mathematics 2023-04-04 Lidia Angeleri Hügel , Francesco Sentieri

Let $H$ be a Hopf algebra. We consider $H$-equivariant modules over a Hopf module category $\mathcal C$ as modules over the smash extension $\mathcal C\# H$. We construct Grothendieck spectral sequences for the cohomologies as well as the…

Rings and Algebras · Mathematics 2020-09-16 Mamta Balodi , Abhishek Banerjee , Samarpita Ray

For any additive functor from modules (or, more generally, from an abelian category with enough projectives or injectives), we construct long sequences tying up together the derived functors, the satellites, and the stabilizations of the…

Representation Theory · Mathematics 2025-04-30 Alex Martsinkovsky

We introduce the notion of support equivalence for (co)module algebras (over Hopf algebras), which generalizes in a natural way (weak) equivalence of gradings. We show that for each equivalence class of (co)module algebra structures on a…

Rings and Algebras · Mathematics 2023-09-14 Ana Agore , Alexey Gordienko , Joost Vercruysse

We construct an "almost involution" assigning a new DG-category to a given one, and use this construction to recover, say, the abelian category of graded modules over the graded ring $R^*$ from the DG-category of DG-modules over a DG-ring…

Category Theory · Mathematics 2025-10-08 Leonid Positselski

We introduce abelian framed bicategories, which are particular framed bicategories that are locally abelian, and show that they are suitable for developing homology and cohomology theories for directed structures. This means in particular…

Category Theory · Mathematics 2026-02-05 Augustin Albert , Jérémy Dubut , Eric Goubault

The paper studies quadratic and Koszul duality for modules over positively graded categories. Typical examples are modules over a path algebra, which is graded by the path length, of a not necessarily finite quiver with relations. We…

Representation Theory · Mathematics 2010-04-02 Volodymyr Mazorchuk , Serge Ovsienko , Catharina Stroppel

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

This chapter sets out preliminaries for the duality theory in later chapters. An underlying idea is that local cohomology functors are higher derived functors of colocalizations (a.k.a.~coreflections). Predominantly well-known facts about…

Algebraic Geometry · Mathematics 2021-06-15 Joseph Lipman

In contrast to the theory of tilting modules, the dual theory lacks a unified definition. Nevertheless, several notions of cotilting modules have been proposed. In this paper, we compare four of the main definitions of cotilting modules…

Representation Theory · Mathematics 2025-12-23 Kamran Divaani-Aazar , Ali Mahin Fallah , Massoud Tousi

We construct from a finitary exact category with duality a module over its Hall algebra, called the Hall module, encoding the first order self-dual extension structure of the category. We study in detail Hall modules arising from the…

Representation Theory · Mathematics 2014-07-14 Matthew B. Young

Let $H$ be a Hopf algebra over a field $k$, and $A$ an $H$-comodule algebra. The categories of comodules and relative Hopf modules are then Grothendieck categories with enough injectives. We study the derived functors of the associated Hom…

Rings and Algebras · Mathematics 2007-05-23 S. Caenepeel , T. Guédénon

For a finite tensor category $\mathcal C$ and a Hopf monad $T:\mathcal C\to \mathcal C$ satisfying certain conditions we describe exact indecomposable left $\mathcal C^T$-module categories in terms of left $\mathcal C$-module categories and…

Quantum Algebra · Mathematics 2014-06-02 Martín Mombelli , Sonia Natale

We give a necessary and sufficient condition in terms of group cohomology for two indecomposable module categories over a group-theoretical fusion category ${\mathcal C}$ to be equivalent. This concludes the classification of such module…

Quantum Algebra · Mathematics 2017-06-20 Sonia Natale

Enomoto and Sakai classified IE-closed subcategories over hereditary algebras via twin rigid modules. However, this classification inherently relies on the vanishing of second extension spaces, thus failing for arbitrary finite-dimensional…

Representation Theory · Mathematics 2026-04-03 Hanpeng Gao , Dajun Liu , Yu-Zhe Liu

We introduce the notion of balanced pair of additive subcategories in an abelian category. We give sufficient conditions under which the balanced pair of subcategories gives rise to equivalent homotopy categories of complexes. As an…

Rings and Algebras · Mathematics 2010-11-23 Xiao-Wu Chen

Let $R$ be an associative ring with identity. This paper investigates the structure of the monomorphism category of large $R$-modules and establishes connections with the category of contravariant functors defined on finitely presented…

Representation Theory · Mathematics 2025-04-11 Rasool Hafezi , Javad Asadollahi , Razieh Vahed , Yi Zhang

The universal property for the B\'enabou bicategory of distributors (although we call them "modules") presented here is somewhat implicitly spread over a series of papers and yet, to my knowledge, does not appear in print. The inclusion of…

Category Theory · Mathematics 2026-03-06 Ross Street

The main source of inspiration for the present paper is the work of R. Rosebrugh and R.J. Wood on constructive complete distributive lattices where the authors employ elegantly the concepts of adjunction and module in their study of ordered…

Category Theory · Mathematics 2010-09-21 Dirk Hofmann