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Related papers: Quasi-cotilting modules and torsion-free classes

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We introduce and study the new concepts of cosilting complexes, cosilting modules and AIR-cotilting modules. We prove that the three concepts AIR-cotilting modules, cosilting modules and quasi-cotilting modules coincide with each other, in…

Rings and Algebras · Mathematics 2016-01-08 Peiyu Zhang , Jiaqun Wei

We study the class of modules, called cosilting modules, which are defined as the categorical duals of silting module. Several characterizations of these modules and connections with silting modules are presented. We prove that Bazzoni…

Rings and Algebras · Mathematics 2017-03-01 Simion Breaz , Flaviu Pop

Recently, tilting and cotilting classes over commutative noetherian rings have been classified in arXiv:1203.0907. We proceed and, for each n-cotilting class C, construct an n-cotilting module inducing C by an iteration of injective…

Commutative Algebra · Mathematics 2014-07-08 Jan Stovicek , Jan Trlifaj , Dolors Herbera

We study the classes of modules which are generated by a silting module. In the case of either hereditary or perfect rings it is proved that these are exactly the torsion $\mathcal{T}$ such that the regular module has a special…

Representation Theory · Mathematics 2017-04-06 Simion Breaz , Jan Žemlička

The R-module functors that are essential for the development of the theory of the linear representations of an affine R-group are the quasi-coherent R-modules and the R-module schemes. The aim of this paper is to study when a quasi-coherent…

Commutative Algebra · Mathematics 2011-11-10 Amelia Álvarez Sánchez , Carlos Sancho de Salas , Pedro Sancho de Salas

In this paper we study cotorsion and torsion pairs induced by cotilting modules. We prove the existence of a strong relationship between the $\Sigma$-pure injectivity of the cotilting module and the property of the induced cotorsion pair to…

Rings and Algebras · Mathematics 2009-05-20 Riccardo Colpi , Francesca Mantese , Alberto Tonolo

In this paper, we characterize quasi-integrable modules, of nonzero level, over twisted affine Lie superalgebras. We show that quasi-integrable modules are not necessarily highest weight modules. We prove that each quasi-integrable module…

Representation Theory · Mathematics 2022-02-02 Malihe Yousofzadeh

The aim of this paper is to describe the classes of strongly flat and weakly cotorsion modules with respect to a multiplicative subset or a finite collection of multiplicative subsets in a commutative ring. The strongly flat modules are…

Commutative Algebra · Mathematics 2019-04-08 Leonid Positselski , Alexander Slavik

To a big n-tilting object in a complete, cocomplete abelian category A with an injective cogenerator we assign a big n-cotilting object in a complete, cocomplete abelian category B with a projective generator, and vice versa. Then we…

Category Theory · Mathematics 2021-01-13 Leonid Positselski , Jan Stovicek

Let R be a ring (not necessarily commutative). A left R-module is said to be cotorsion if Ext 1 R (G, M) = 0 for any flat R-module G. It is well known that each pure-injective left R-module is cotorsion, but the converse does not hold: for…

Rings and Algebras · Mathematics 2016-03-25 Francois Couchot

Motivated by the study of (m,n)-quasitilted algebras, which are the piecewise hereditary algebras obtained from quasitilted algebras of global dimension two by a sequence of (co)tiltings involving n-1 tilting modules and m-1 cotilting…

Representation Theory · Mathematics 2017-09-22 Diane Castonguay , Edson Ribeiro Alvares , Patrick Le Meur , Tanise Carnieri Pierin

A relationship between curved differential algebras and corings is established and explored. In particular it is shown that the category of semi-free curved differential graded algebras is equivalent to the category of corings with…

Rings and Algebras · Mathematics 2013-01-28 Tomasz Brzeziński

An important result in tilting theory states that a class of modules over a ring is a tilting class if and only if it is the Ext-orthogonal class to a set of compact modules of bounded projective dimension. Moreover, cotilting classes are…

Representation Theory · Mathematics 2017-04-24 Frederik Marks , Jorge Vitória

We develop theory of (possibly large) cotilting objects of injective dimension at most one in general Grothendieck categories. We show that such cotilting objects are always pure-injective and that they characterize the situation where the…

Algebraic Geometry · Mathematics 2021-11-29 Pavel Čoupek , Jan Šťovíček

The notion of cosilting module was recently introduced as a generalization of the concept of cotilting module. In this paper, it is introduced the notion of finitely cosilting module, i.e. a cosilting module with some finitness conditions,…

Rings and Algebras · Mathematics 2017-12-05 Flaviu Pop

We show that if a class of modules is closed under pure quotients, then it is precovering if and only if it is covering, and this happens if and only if it is closed under direct sums. This is inspired by a dual result by Rada and…

Rings and Algebras · Mathematics 2007-05-23 Henrik Holm , Peter Jorgensen

We classify all tilting classes over an arbitrary commutative ring via certain sequences of Thomason subsets of the spectrum, generalizing the classification for noetherian commutative rings by…

Commutative Algebra · Mathematics 2020-03-24 Michal Hrbek , Jan Šťovíček

Let X be the toric scheme over a ring R associated with a fan Sigma. It is shown that there are a group B, a B-graded R-algebra S and a graded ideal I of S such that there is an essentially surjective, exact functor ~ from the category of…

Algebraic Geometry · Mathematics 2014-04-03 Fred Rohrer

It is demonstrated that any almost-tilting module over a gentle algebra is indeed partial-tilting, meaning it can be completed as a tilting module. Furthermore, such a module has at most $2n$ possible complements, thereby confirming a…

Representation Theory · Mathematics 2025-05-01 Wen Chang

Let $R$ be a commutative ring. An $R$-module $M$ is called a semi-regular $w$-flat module if $\Tor_1^R(R/I,M)$ is $\GV$-torsion for any finitely generated semi-regular ideal $I$. In this article, we show that the class of semi-regular…

Commutative Algebra · Mathematics 2023-03-07 Xiaolei Zhang
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