English
Related papers

Related papers: Weakly Sigma-cotorsion rings

200 papers

Let $\mathcal{P}$ be the class of rings for which every indecomposable right module is pure-projective or pure-injective. When $R$ is a Noetherian local commutative ring of maximal ideal $P$, it is proven that $R\in\mathcal{P}$ if and only…

Rings and Algebras · Mathematics 2025-07-08 François Couchot

Let $R$ be a commutative Noetherian ring, $\Phi$ a system of ideals of $R$ and $I\in \Phi$. Let $M$ be an $R$-module (not necessary $I$-torsion) such that $\dim M\leq 1$, then the $R$-module $\Ext^i_{R}(R/I, M)$ is weakly Laskerian, for all…

Commutative Algebra · Mathematics 2017-07-24 Moharram Aghapournahr

In this paper, we introduce and study the class $S$-$\mathcal{F}$-ML of $S$-Mittag-Leffler modules with respect to all flat modules. We show that a ring $R$ is $S$-coherent if and only if $S$-$\mathcal{F}$-ML is closed under submodules. As…

Commutative Algebra · Mathematics 2021-11-29 Wei Qi , Xiaolei Zhang , Wei Zhao

This paper generalize the idea of the authors in \cite{Bennis and Mahdou1}. Namely, we define and study a particular case of modules with Gorenstein projective, injective, and flat dimension less or equal than $n\geq 0$, which we call,…

Commutative Algebra · Mathematics 2009-04-28 Najib Mahdou , Mohammed Tamekkante

We define topologically semiperfect (complete, separated, right linear) topological rings and characterize them by equivalent conditions. We show that the endomorphism ring of a module, endowed with the finite topology, is topologically…

Rings and Algebras · Mathematics 2024-03-06 Leonid Positselski , Jan Stovicek

Let $R$ be a ring and denote by $\mathcal{FM}$ the class of all flat and Mittag-Leffler left $R$-modules. In \cite{BazzoniStovicek2} it is proved that, if $R$ is countable, the orthogonal class of $\mathcal{FM}$ consists of all cotorsion…

Rings and Algebras · Mathematics 2017-01-17 Manuel Cortés-Izurdiaga

Gorenstein homological dimensions are refinements of the classical homological dimensions, and finiteness singles out modules with amenable properties reflecting those of modules over Gorenstein rings. As opposed to their classical…

Commutative Algebra · Mathematics 2007-05-23 L. Winther Christensen , A. Frankild , H. Holm

Baer's Criterion of injectivity implies that injectivity of a module is a factorization property w.r.t. a single monomorphism. Using the notion of a cotorsion pair, we study generalizations and dualizations of factorization properties in…

Rings and Algebras · Mathematics 2019-12-10 Jan Šaroch , Jan Trlifaj

We present a new method for combining two cotorsion pairs to obtain an abelian model structure and we apply it to construct and study a new model structure on left $R$-modules over a left coherent ring $R$. Its class of fibrant objects is…

Rings and Algebras · Mathematics 2026-02-11 James Gillespie

In this paper, we introduce the notion of weak core and central weak core inverse in a {\it proper $*$-ring}. We further elaborate on these two classes by producing a few representations and characterizations of the weak core and central…

Rings and Algebras · Mathematics 2023-08-25 Jajati Keshari Sahoo , Ratikanta Behera , Sourav Das , R. N. Mohapatra , Sunil Kumar Prajapati

Given a Henselian and Japanese discrete valuation ring $A$ and a flat and projective $A$-scheme $X$, we follow the approach of Biswas-dos Santos to introduce a full subcategory of coherent modules on $X$ which is then shown to be Tannakian.…

Algebraic Geometry · Mathematics 2019-04-25 Phung Ho Hai , Joao Pedro dos Santos

Let $V$ be a complete discrete valuation ring with residue field $k$ of positive characteristic and with fraction field $K$ of characteristic 0. We clarify the analysis behind the Monsky--Washnitzer completion of a commutative $V$-algebra…

Algebraic Geometry · Mathematics 2019-04-30 Guillermo Cortiñas , Joachim Cuntz , Ralf Meyer , Georg Tamme

In this paper, we introduce and study the notions of $\tau_q$-flat modules and $\tau_q$-coheret rings. First, by investigating the Nagata rings of $\tau_q$-torsion theory, we show that the small finitistic dimensions of T$(R[x])$ are all…

Commutative Algebra · Mathematics 2022-09-28 Xiaolei Zhang , Wei Qi

The structure of cyclically pure injective modules over a commutative ring $R$ is investigated and several characterizations for them are presented. In particular, we prove that a module $D$ is cyclically pure injective if and only if $D$…

Commutative Algebra · Mathematics 2007-05-23 Kamran Divaani-Aazar , Mohammad Ali Esmkhani , Massoud Tousi

We classify finitely generated modules over a class of algebras introduced in the authors' Ph.D thesis, called complete gentle algebras. These rings generalise the finite-dimensional gentle algebras introduced by Assem and Skowro\'{n}ski,…

Representation Theory · Mathematics 2021-07-21 Raphael Bennett-Tennenhaus

Let $R$ be an associative ring with identity. A unital right $R$-module $M$ is called strongly finite dimensional if Sup$\{{\rm G.dim} (M/N) | N\leq M\} < +\infty$. Properties of strongly finite dimensional modules are explored. It is also…

Rings and Algebras · Mathematics 2007-05-23 Liang Shen , Jianlong Chen

Let R be a subring of the rationals. We want to investigate self splitting R-modules G that is Ext_R(G,G)=0 holds and follow Schultz to call such modules splitters. Free modules and torsion-free cotorsion modules are classical examples for…

Logic · Mathematics 2007-05-23 Ruediger Goebel , Saharon Shelah

Our purpose in this work is multifold. First, we provide general criteria for the finiteness of the projective and injective dimensions of a finite module $M$ over a (commutative) Noetherian ring $R$. Second, in the other direction, we…

Commutative Algebra · Mathematics 2024-05-02 Souvik Dey , Rafael Holanda , Cleto B. Miranda-Neto

It is proved that, for a left hereditary ring, an arbitrary left module has a representation in the form of the direct sum of a stable left module and indecomposable projective left modules (if and only if an arbitrary left module has a…

Rings and Algebras · Mathematics 2023-02-23 Dali Zangurashvili

A partition of the set of unary pp formulas into four regions is presented, which has a bearing on various structural properties of modules. The machinery developed allows for applications to IF, weakly coherent, nonsingular, and reduced…

Rings and Algebras · Mathematics 2021-11-04 Philipp Rothmaler