English
Related papers

Related papers: Intrinsic Schreier split extensions

200 papers

We axiomatically define (pre-)Hilbert categories. The axioms resemble those for monoidal Abelian categories with the addition of an involutive functor. We then prove embedding theorems: any locally small pre-Hilbert category whose monoidal…

Category Theory · Mathematics 2010-08-05 Chris Heunen

We extend the definitions and main properties of graded extensions to the category of locally compact groupoids endowed with involutions. We introduce Real \v{C}ech cohomology, which is an equivariant-like cohomology theory suitable for the…

Operator Algebras · Mathematics 2012-02-07 El-kaïoum M. Moutuou

We consider monoids equipped with a compatible quantale valued relation, to which we call quantale enriched monoids, and study semidirect products of such structures. It is well-known that semidirect products of monoids are closely related…

Group Theory · Mathematics 2024-06-24 Célia Borlido

We propose a new framework for the study of homological properties for (compactly generated) triangulated categories such as regularity, finiteness of global or finitistic dimension, gorensteinness or injective generation and the relation…

Representation Theory · Mathematics 2025-12-23 Panagiotis Kostas , Chrysostomos Psaroudakis , Jorge Vitória

We study simple and projective modules of a certain class of Ehresmann semigroups, a well-studied generalization of inverse semigroups. Let $S$ be a finite right (left) restriction Ehresmann semigroup whose corresponding Ehresmann category…

Representation Theory · Mathematics 2021-03-09 Stuart Margolis , Itamar Stein

As an appropriate generalisation of the features of the classical (Schein) theory of representations of inverse semigroups in $\mathscr{I}_{X}$, a theory of representations of inverse semigroups by homomorphisms into complete atomistic…

Group Theory · Mathematics 2021-02-22 D. G. FitzGerald

We introduce a diagrammatic monoidal category, the spin Brauer category, that plays the same role for the spin and pin groups as the Brauer category does for the orthogonal groups. In particular, there is a full functor from the spin Brauer…

Representation Theory · Mathematics 2025-05-14 Peter J. McNamara , Alistair Savage

A general result relating skew monoidal structures and monads is proved. This is applied to quantum categories and bialgebroids. Ordinary categories are monads in the bicategory whose morphisms are spans between sets. Quantum categories…

Category Theory · Mathematics 2014-11-10 Stephen Lack , Ross Street

Covariant Hom-bimodules are introduced and the structure theory of them in the Hom-setting is studied in a detailed way. The category of bicovariant Hom-bimodules is proved to be a (pre)braided monoidal category and its structure theory is…

Quantum Algebra · Mathematics 2019-05-28 Serkan Karaçuha

The structure of monoidal categories in which every arrow is invertible is analyzed in this paper, where we develop a 3-dimensional Schreier-Grothendieck theory of non-abelian factor sets for their classification. In particular, we state…

Category Theory · Mathematics 2012-12-19 María Calvo , Antonio M. Cegarra , Benjamín A. Heredia

We develop Morita theory of monoids in a closed symmetric monoidal category, in the context of enriched category theory.

Category Theory · Mathematics 2024-10-23 Jaehyeok Lee , Jae-Suk Park

We introduce a general framework, based on \'etale topological categories, for studying discrete restriction semigroups and their algebras. Generalizing Paterson's universal groupoid of an inverse semigroup, we define the universal category…

Rings and Algebras · Mathematics 2025-11-07 Ganna Kudryavtseva

We prove that the homotopy theory of parsummable categories (as defined by Schwede) with respect to the underlying equivalences of categories is equivalent to the usual homotopy theory of symmetric monoidal categories. In particular, this…

Category Theory · Mathematics 2021-05-13 Tobias Lenz

We define Euler characteristic of a category enriched by a monoidal model category. If a monoidal model category V is equipped with Euler characteristic that is compatible with weak equivalences and fibrations in V, then our Euler…

Category Theory · Mathematics 2016-11-25 Kazunori Noguchi , Kohei Tanaka

Building on structure observed in equivariant homotopy theory, we define an equivariant generalization of a symmetric monoidal category: a $G$-symmetric monoidal category. These record not only the symmetric monoidal products but also…

Algebraic Topology · Mathematics 2016-10-12 Michael A. Hill , Michael J. Hopkins

In this article, we introduce the concepts of graded $s$-prime submodules which is a generalization of graded prime submodules. We study the behavior of this notion with respect to graded homomorphisms, localization of graded modules,…

Rings and Algebras · Mathematics 2020-09-15 Hicham Saber , Tariq Alraqad , Rashid Abu-Dawwas

It is a well-known fact that the category $\mathsf{Cat}(\mathbf{C})$ of internal categories in a category $\mathbf{C}$ has a description in terms of crossed modules, when $\mathbf{C}=\mathbf{Gr}$ is the category of groups. The proof of this…

Category Theory · Mathematics 2024-01-04 Ilia Pirashvili

We investigate the concept of definable, or inner, automorphism in the logical setting of partial Horn theories. The central technical result extends a syntactical characterization of the group of such automorphisms (called the covariant…

Logic in Computer Science · Computer Science 2021-02-23 Pieter Hofstra , Jason Parker , Philip J. Scott

We observe that the process of associating an action to any Schreier extension of monoids with commutative and cancellative kernel is functorial. We show that this functor is a generalisation of the direction functor, used to give a…

Category Theory · Mathematics 2026-02-25 Stefano Ambra , Andrea Montoli , Diana Rodelo

The central object studied in this paper is a multiplier bimonoid in a braided monoidal category C. Adapting the philosophy of Janssen and Vercruysse, and making some mild assumptions on the category C, we consider a category M whose…

Category Theory · Mathematics 2019-07-08 Gabriella Böhm , Stephen Lack