English
Related papers

Related papers: A characterization of 2-fold torsion classes induc…

200 papers

Inspired by tau-tilting theory [AIR], we introduce the notion of nu-stable support tau-tilting modules. For any finite dimensional selfinjective algebra {\Lambda}, we give bijections between two-term tilting complexes in Kb(proj {\Lambda}),…

Representation Theory · Mathematics 2013-12-04 Yuya Mizuno

The study of modules over a finite von Neumann algebra ${\mathcal A}$ can be advanced by the use of torsion theories. In this work, some torsion theories for ${\mathcal A}$ are presented, compared and studied. In particular, we prove that…

Rings and Algebras · Mathematics 2007-05-23 Lia Vas

Torsion theories are a pinnacle in the theory of abelian categories. They are a generalization of torsion abelian groups and in this generalization one of the most studied is that whose torsionfree class consists of nonsingular modules. To…

In this paper we determine the torsion free rank of the group of endotrivial modules for any finite group of Lie type, in both defining and non-defining characteristic. On our way to proving this, we classify the maximal rank $2$ elementary…

Group Theory · Mathematics 2022-07-20 Jon F. Carlson , Jesper Grodal , Nadia Mazza , Daniel K. Nakano

Torsion theories play an important role in abelian categories and they have been widely studied in the last sixty years. In recent years, with the introduction of pretorsion theories, the definition has been extended to general…

Category Theory · Mathematics 2024-07-17 Federico Campanini , Francesca Fedele

$\tau$-rigid modules are essential in the $\tau$-tilting theory introduced by Adachi, Iyama and Reiten. In this paper, we give equivalent conditions for Iwanaga-Gorenstein algebras with self-injective dimension at most one in terms of…

Representation Theory · Mathematics 2019-05-07 Zongzhen Xie , Libo Zan , Xiaojin Zhang

Higher homological algebra was introduced by Iyama. It is also known as $n$-homological algebra where $n \geq 2$ is a fixed integer, and it deals with $n$-cluster tilting subcategories of abelian categories. All short exact sequences in…

Representation Theory · Mathematics 2015-08-13 Peter Jorgensen

We study (relative) K-Mittag-Leffler modules, with emphasis on the class K of absolutely pure modules. A final goal is to describe the K-Mittag-Leffler abelian groups as those that are, modulo their torsion part, aleph_1-free, Cor.6.12.…

Rings and Algebras · Mathematics 2013-01-08 Philipp Rothmaler

Let R be a commutative noetherian ring. Denote by mod R the category of finitely generated R-modules. In this paper, we study n-torsionfree modules in the sense of Auslander and Bridger, by comparing them with n-syzygy modules, and modules…

Commutative Algebra · Mathematics 2021-01-13 Souvik Dey , Ryo Takahashi

This paper introduces the notion of extriangulated length categories, whose prototypical examples include abelian length categories and bounded derived categories of finite dimensional algebras with finite global dimension. We prove that an…

Representation Theory · Mathematics 2025-05-15 Li Wang , Jiaqun Wei , Haicheng Zhang , Panyue Zhou

We study (support) $\tau$-tilting modules over the trivial extensions of finite dimensional algebras. More precisely, we construct two classes of (support)$\tau$-tilting modules in terms of the adjoint functors which extend and generalize…

Representation Theory · Mathematics 2022-02-21 Zhi-Wei Li , Xiaojin Zhang

We introduce the notion of torsion-simple objects in an abelian category: these are the objects which are always either torsion or torsion-free with respect to any torsion pair. We present some general results concerning their properties,…

Representation Theory · Mathematics 2023-12-08 Sergio Pavon

We study torsion torsionfree(=TTF) triples in abelian and triangulated categories. (Notice that TTF triples in a triangulated category are essentially in bijection with recollement data for this triangulated category.) In particular, we…

Representation Theory · Mathematics 2008-01-04 Pedro Nicolas

We give a construction of Gorenstein projective $\tau$-tilting modules in terms of tensor products of modules. As a consequence, we give a class of non-self-injective algebras admitting non-trivial Gorenstein projective $\tau$-tilting…

Representation Theory · Mathematics 2022-01-13 Zhi-Wei Li , Xiaojin Zhang

In this paper we describe a homotopy torsion theory in the category of small symmetric monoidal categories. Thanks to the use of natural isomorphisms as basis for the nullhomotopy structure, this homotopy torsion theory enjoys some…

Category Theory · Mathematics 2025-04-29 Mariano Messora

We work with $FI$-modules over a small preadditive category $\mathcal R$, viewed as a ring with several objects. Our aim is to study torsion theories for $FI$-modules. We are especially interested in torsion theories on finitely generated…

Category Theory · Mathematics 2020-02-04 Abhishek Banerjee

We establish a bijection between torsion pairs in the category of finite-dimensional modules over a finite-dimensional algebra A and pairs (Z, I) formed by a closed rigid set Z in the Ziegler spectrum of A and a set I of indecomposable…

Representation Theory · Mathematics 2024-03-04 Lidia Angeleri Hügel , Rosanna Laking , Francesco Sentieri

In the category of finitely generated modules over an artinian ring, we classify all the abelian exact subcategories closed under predecessors or, equivalently, all the split torsion pairs with torsion-free class closed under quotients.

Rings and Algebras · Mathematics 2007-05-23 Ibrahim Assem , Manuel Saorin

We give a characterization of $\tau$-rigid modules over Auslander algebras in terms of projective dimension of modules. Moreover, we show that for an Auslander algebra $\Lambda$ admitting finite number of non-isomorphic basic tilting…

Rings and Algebras · Mathematics 2017-02-28 Xiaojin Zhang

A torsion class $\mathcal{T}$ of the module category $\operatorname{\mathsf{mod}} A$ of a finite dimensional algebra $A$ over a field $K$ is said to be compact if there exists a module $M \in \operatorname{\mathsf{mod}} A$ such that…

Representation Theory · Mathematics 2026-04-07 Sota Asai