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Related papers: Morita theory of comodules over corings

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We extend Morita theory to abelian categories by using wide Morita contexts. Several equivalence results are given for wide Morita contexts between abelian categories, widely extending equivalence theorems for categories of modules and…

Rings and Algebras · Mathematics 2007-05-23 N. Chifan , S. Dascalescu , C. Nastasescu

For any ring R the category of monomorphisms is a full subcategory of the morphsim category over R, where the latter is equivalent to the module category of the triangular matrix ring with entries the ring R. In this work, we consider the…

Representation Theory · Mathematics 2016-12-13 Nan Gao , Chrysostomos Psaroudakis

This paper is a follow-up to arXiv:2212.09639. We consider two algebraic settings of comodules over a coring and contramodules over a topological ring with a countable base of two-sided ideals. These correspond to two (noncommutative)…

Rings and Algebras · Mathematics 2024-11-06 Leonid Positselski

We study the class of rings $R$ for which every direct sum of injective $R$-modules is cotorsion. We call them weakly $\Sigma$-cotorsion rings. The defining property might be seen as the dual of Chase's characterization of coherence in…

Rings and Algebras · Mathematics 2026-02-13 Manuel Cortés-Izurdiaga , Sergio Estrada , José Manuel Fresneda

We study rational modules over complete path and monomial algebras, and the problem of when rational modules over the dual $C^*$ of a coalgebra $C$ are closed under extensions, equivalently, when is the functor $Rat$ a torsion functor. We…

Representation Theory · Mathematics 2016-01-01 M. C. Iovanov

Let A be a commutative ring, and \a a weakly proregular ideal in A. This includes the noetherian case: if A is noetherian then any ideal in it is weakly proregular; but there are other interesting examples. In this paper we prove the MGM…

Commutative Algebra · Mathematics 2012-10-17 Marco Porta , Liran Shaul , Amnon Yekutieli

In their previous work, S. Koenig, S. Ovsienko and the second author showed that every quasi-hereditary algebra is Morita equivalent to the right algebra, i.e. the opposite algebra of the left dual, of a coring. Let $A$ be an associative…

Representation Theory · Mathematics 2017-12-20 Agnieszka Bodzenta , Julian Külshammer

If two cluster-tilting objects of an acyclic cluster category are related by a mutation, then their endomorphism algebras are nearly-Morita equivalent [Buan-Marsh-Reiten], i.e. their module categories are equivalent "up to a simple module".…

Representation Theory · Mathematics 2020-12-21 Bethany Marsh , Yann Palu

We discuss what it means for a symmetric monoidal category to be a module over a commutative semiring category. Each of the categories of (1) cartesian monoidal categories, (2) semiadditive categories, and (3) connective spectra can be…

Category Theory · Mathematics 2018-08-29 John D. Berman

We present the rudiments of the Morita theory of module systems (over semirings), paralleling the classical Morita theory over associative rings.

Rings and Algebras · Mathematics 2019-03-07 Louis Rowen

This paper is an exposition of the so-called injective Morita contexts (in which the connecting bimodule morphisms are injective) and Morita $\alpha$contexts (in which the connecting bimodules enjoy some local projectivity in the sense of…

Rings and Algebras · Mathematics 2007-08-22 J. Y. Abuhlail , S. K. Nauman

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

Prime objects were defined as generalization of simple objects in the categories of rings (modules). In this paper we introduce and investigate what turns out to be a suitable generalization of simple corings (simple comodules), namely…

Rings and Algebras · Mathematics 2007-05-23 Jawad A. Abuhlail

For a commutative ring $A$, we have the category of (bounded-below) chain complexes of $A$-modules $Ch_{+}(A\mymod)$, a closed symmetric monoidal category with a compatible stable Quillen model structure. The associated homotopy category is…

Algebraic Geometry · Mathematics 2020-06-30 Shai Haran

We define a strong Morita-type equivalence $\sim _{\sigma \Delta }$ for operator algebras. We prove that $A\sim _{\sigma \Delta }B$ if and only if $A$ and $B$ are stably isomorphic. We also define a relation $\subset _{\sigma \Delta }$ for…

Operator Algebras · Mathematics 2018-12-12 G. K. Eleftherakis

We obtain a characterization of left perfect rings via superstability of the class of flat left modules with pure embeddings. $\mathbf{Theorem.}$ For a ring $R$ the following are equivalent. - $R$ is left perfect. - The class of flat left…

Logic · Mathematics 2020-09-11 Marcos Mazari-Armida

In this note we consider different versions of coinduction functors between categories of comodules for corings induced by a morphism of corings. In particular we introduce a new version of the coinduction functor in the case of locally…

Rings and Algebras · Mathematics 2007-05-23 Jawad Abuhlail

We develop a general framework for the study of strong Morita equivalence in which $C^*$-algebras and hermitian star products on Poisson manifolds are treated in equal footing. We compare strong and ring-theoretic Morita equivalences in…

Quantum Algebra · Mathematics 2007-05-23 Henrique Bursztyn , Stefan Waldmann

We introduce bounded category forcing axioms for well-behaved classes $\Gamma$. These are strong forms of bounded forcing axioms which completely decide the theory of some initial segment of the universe $H_{\lambda_\Gamma^+}$ modulo…

Logic · Mathematics 2021-01-11 David Aspero , Matteo Viale

Let $R$ be a commutative ring with unity and $C$ be an $R$-coalgebra. The ring $R$ is clean if every $ r\in R $ is the sum of a unit and an idempotent element of $R$. An $R$-module $M$ is clean if the endomorphism ring of $M$ over $R$ is…

Rings and Algebras · Mathematics 2022-04-08 Nikken Prima Puspita , Indah Emilia Wijayanti , Budi Surodjo