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Related papers: Pullback Crossed Modules in the Category of Racks

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Span categories provide an abstract framework for formalizing mathematical models of certain systems. The mathematical descriptions of some systems, such as classical mechanical systems, require categories that do not have pullbacks, and…

Category Theory · Mathematics 2023-03-22 David Weisbart , Adam Yassine

Containers represent a wide class of type constructions relevant for functional programming and (co)inductive reasoning. Indexed containers generalize this notion to better fit the scope of dependently typed programming. When interpreting…

Logic in Computer Science · Computer Science 2025-10-01 Michele De Pascalis , Tarmo Uustalu , Niccolò Veltrì

We introduce the category HG, whose objects are topological groupoids endowed with compatible measure theoretic data: a Haar system and a measure on the unit space. We then define and study the notion of weak-pullback in the category of…

Functional Analysis · Mathematics 2011-01-18 Aviv Censor , Daniele Grandini

A notion of a coring extension is defined and it is related to the existence of an additive functor between comodule categories that factorises through forgetful functors. This correspondence between coring extensions and factorisable…

Rings and Algebras · Mathematics 2008-07-31 Tomasz Brzezinski

Let $R$ be an associative ring with identity. This paper investigates the structure of the monomorphism category of large $R$-modules and establishes connections with the category of contravariant functors defined on finitely presented…

Representation Theory · Mathematics 2025-04-11 Rasool Hafezi , Javad Asadollahi , Razieh Vahed , Yi Zhang

Some aspects of basic category theory are developed in a finitely complete category $\C$, endowed with two factorization systems which determine the same discrete objects and are linked by a simple reciprocal stability law. Resting on this…

Category Theory · Mathematics 2008-02-06 Claudio Pisani

In this paper we present some applications of Ann-category theory to classification of crossed bimodules over rings, classification of ring extensions of the type of a crossed bimodule.

Category Theory · Mathematics 2013-01-07 Nguyen Tien Quang , Pham Thi Cuc

For a finite braided tensor category we introduce its Picard crossed module consisting of the group of invertible module categories and the group of braided tensor autoequivalences. We describe the Picard crossed module in terms of braided…

Quantum Algebra · Mathematics 2012-02-02 Alexei Davydov , Dmitri Nikshych

This is the second part of the paper. Results of the first part about crossed modules are applied here to study of quantum groups in braided categories. Correct cross product in the class of quantum braided groups is built. Criterion when…

High Energy Physics - Theory · Physics 2008-02-03 Yuri Bespalov

We develop a categorical framework for studying graphs of groups and their morphisms, with emphasis on pullbacks. More precisely, building on classical work by Serre and Bass, we give an explicit construction of the so-called…

Group Theory · Mathematics 2026-04-15 Jordi Delgado , Marco Linton , Jone Lopez de Gamiz Zearra , Mallika Roy , Pascal Weil

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

This is the second part of a series of three strongly related papers in which three equivalent structures are studied: - internal categories in categories of monoids; defined in terms of pullbacks relative to a chosen class of spans -…

Category Theory · Mathematics 2018-03-13 Gabriella Böhm

We decompose the crossed product functor for actions of crossed modules of locally compact groups on C*-algebras into more elementary constructions: taking crossed products by group actions and fibres in C*-algebras over topological spaces.…

Operator Algebras · Mathematics 2015-06-02 Alcides Buss , Ralf Meyer

The homotopy theory of higher categorical structures has become a relevant part of the machinery of algebraic topology and algebraic K-theory, and this paper contains contributions to the study of the relationship between B\'enabou's…

Category Theory · Mathematics 2014-04-11 A. M. Cegarra , B. A. Heredia , J. Remedios

We study the circumstances under which one can reconstruct a stack from its associated functor of isomorphism classes. This is possible surprisingly often: we show that many of the standard examples of moduli stacks are determined by their…

Algebraic Geometry · Mathematics 2018-06-18 Max Lieblich , Brian Osserman

Categorical aspects of the theory of modules over trusses are studied. Tensor product of modules over trusses is defined and its existence established. In particular, it is shown that bimodules over trusses form a monoidal category. Truss…

Rings and Algebras · Mathematics 2022-03-31 Tomasz Brzeziński , Bernard Rybołowicz , Paolo Saracco

In [arXiv:1509.02937], the notion of a module tensor category was introduced as a braided monoidal central functor $F\colon \mathcal{V}\longrightarrow \mathcal{T}$ from a braided monoidal category $\mathcal{V}$ to a monoidal category…

Category Theory · Mathematics 2023-11-22 Sebastian Heinrich

The notion of crossed modules for Lie 2-algebras is introduced. We show that, associated to such a crossed module, there is a strict Lie 3-algebra structure on its mapping cone complex and a strict Lie 2-algebra structure on its…

Rings and Algebras · Mathematics 2014-03-03 Honglei Lang , Zhangju Liu

We classify the module categories over the double (possibly twisted) of a finite group.

Quantum Algebra · Mathematics 2007-05-23 Victor Ostrik

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