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Related papers: Morita Contexts for Corings and Equivalences

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We develop a Galois (descent) theory for comonads within the framework of bicategories. We give generalizations of Beck's theorem and the Joyal-Tierney theorem. Many examples are provided, including classical descent theory, Hopf-Galois…

Rings and Algebras · Mathematics 2007-11-26 Jose Gomez-Torrecillas , Joost Vercruysse

We introduce the notion of bi-monoid in general monoidal category generalizing by this the notion of bialgebra. In the case of bimodules over a noncommutative algebra, we obtain a compatibility condition between ring and coring whenever…

Rings and Algebras · Mathematics 2007-05-23 L. El Kaoutit

In this article we defined and studied quasi-finite comodules, the cohom functors for coalgebras over rings. linear functors between categories of comodules are also investigated and it is proved that good enough linear functors are nothing…

Rings and Algebras · Mathematics 2007-05-23 Khaled Al-Takhman

This paper investigates coherent-like conditions and related properties that a trivial extension might inherit from the ground ring over some classes of modules. It captures previous results dealing primarily with coherence, and also…

Commutative Algebra · Mathematics 2007-05-23 S. Kabbaj , N. Mahdou

We focus our attention to the set $\gl{\coring{C}}$ of grouplike elements of a coring $\coring{C}$ over a ring $A$. We do some observations on the actions of the groups $U(A)$ and $\aut{\coring{C}}$ of units of $A$ and of automorphisms of…

Rings and Algebras · Mathematics 2009-01-28 L. El Kaoutit , J. Gomez-Torrecillas

Characteristic properties of corings with a grouplike element are analysed. Associated differential graded rings are studied. A correspondence between categories of comodules and flat connections is established. A generalisation of the…

Rings and Algebras · Mathematics 2007-05-23 Tomasz Brzezinski

Given a ring $A$ and an $A$-coring $\cC$ we study when the forgetful functor from the category of right $\cC$-comodules to the category of right $A$-modules and its right adjoint $-\otimes_A\cC$ are separable. We then proceed to study when…

Rings and Algebras · Mathematics 2016-09-07 Tomasz Brzezinski

We provide concrete models for generalized morphisms and Morita equivalences of topological 2-groupoids by introducing the notions of crossings and crossed extensions of groupoid crossed modules. A systematic study of these objects is…

Algebraic Topology · Mathematics 2018-02-07 El-kaïoum M. Moutuou

In this article we revisit the theory of homotopic Hopf-Galois extensions introduced in arXiv:0902.3393v2 [math.AT], in light of the homotopical Morita theory of comodules established in arXiv:1411.6517 [math.AT]. We generalize the theory…

Algebraic Topology · Mathematics 2016-01-05 Alexander Berglund , Kathryn Hess

We show that the category of corings over a fixed base ring with local units is equivalent to the category of comonads in (right) unital modules whose underlying functors preserve inductive limits. Changing base rings, we prove a…

Rings and Algebras · Mathematics 2009-04-27 L. El Kaoutit

Formal concept analysis (FCA) is built on a special type of Galois connections called polarities. We present new results in formal concept analysis and in Galois connections by presenting new Galois connection results and then applying…

Other Computer Science · Computer Science 2013-09-23 Jeffrey T. Denniston , Austin Melton , Stephen E. Rodabaugh

We study aspects of gauge theory on tori which are a consequences of Morita equivalence. In particular we study the behavior of gauge theory on noncommutative tori for arbitrarily close rational values of Theta. For such values of Theta,…

High Energy Physics - Theory · Physics 2010-02-03 Zachary Guralnik , Jan Troost

We consider the following problem: Under what assumptions do one or more of the following are equivalent for a ring $R$: (A) $R$ is Morita equivalent to a ring with involution, (B) $R$ is Morita equivalent to a ring with an…

Rings and Algebras · Mathematics 2015-04-07 Uriya A. First

Properties of (most general) non-commutative torsors or A-B torsors are analysed. Starting with pre-torsors it is shown that they are equivalent to a certain class of Galois extensions of algebras by corings. It is shown that a class of…

Quantum Algebra · Mathematics 2012-01-27 Gabriella Böhm , Tomasz Brzezinski

We compare several quasi-Frobenius-type properties for corings that appeared recently in literature and provide several new characterizations for each of these properties. By applying the theory of Galois comodules with a firm coinvariant…

Rings and Algebras · Mathematics 2008-06-10 Joost Vercruysse

A surjective Morita context connecting semigroups $S$ and $T$ yields a Morita semigroup and a strict local isomorphism from it onto $S$ along which idempotents lift. We describe strong Morita equivalence of firm semigroups in terms of…

Group Theory · Mathematics 2021-08-27 Alvin Lepik

Under semi-weak and weak compatibility of bimodules, we establish sufficient and necessary conditions of Gorenstein-projective modules over rings of Morita contexts with one bimodule homomorphism zero. This generalises and extends results…

Representation Theory · Mathematics 2022-08-24 Qianqian Guo , Changchang Xi

It is shown that any finite complete covering of a non-commutative algebra in the sense of Calow and Matthes (J. Geom. Phys. 32 (2000), 114--165) gives rise to a Galois coring.

Rings and Algebras · Mathematics 2007-05-23 Tomasz Brzezinski , Adam P Wrightson

We study Morita equivalence in the context of quantales with identity, in the wake of Katsov and Nam's analogous work on semirings. Among a number of other results, we prove a characterization of Morita equivalence and an…

Category Theory · Mathematics 2025-10-10 Moacyr Rodrigues , Ciro Russo

In this paper, we extend the study of graded equivalences to the case of general idempotent graded rings. We prove that the existence of a graded equivalence between two categories of graded torsion-free unital modules may be characterized…

Rings and Algebras · Mathematics 2026-04-15 Mikhailo Dokuchaev , Juan Jacobo Simón