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Related papers: Crossed modules of monoids I. Relative categories

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We present here definitions and constructions basic for the theory of monoidal and tensor categories. We provide references to the original sources, whenever possible. Group-theoretical categories are used as examples

Category Theory · Mathematics 2023-11-13 Alexei Davydov

We introduce semidirect products of skew monoidal categories as a categorification of semidirect products of monoids (or, perhaps more familiarly, of groups). We also discuss how this construction interacts with monoidal, autonomous and…

Category Theory · Mathematics 2016-07-05 Ben Fuller

The centre of a monoidal category is a braided monoidal category. Monoidal categories are monoidal objects (or pseudomonoids) in the monoidal bicategory of categories. This paper provides a universal construction in a braided monoidal…

Category Theory · Mathematics 2007-05-23 Ross Street

This is an overview of the idea of a crossed module. For a group, the triple that consists of the group, its group of automorphisms, and the canonical homomorphism from the group to its group of automorphisms constitutes a crossed module.…

Group Theory · Mathematics 2024-03-26 Johannes Huebschmann

A groupoid is a small category in which all morphisms are isomorphisms. An inductive groupoid is a specialised groupoid whose object set is a regular biordered set and the morphisms admit a partial order. A normal category is a specialised…

Category Theory · Mathematics 2021-09-14 P. A. Azeef Muhammed , Mikhail V. Volkov

We define the monoidal category $(Poly_E,y,\triangleleft)$ of polynomials under composition in any category $E$ with finite limits, including both cartesian and vertical morphisms of polynomials, and generalize to this setting the Dirichlet…

Category Theory · Mathematics 2023-05-22 Brandon T. Shapiro , David I. Spivak

In that paper, we prove that the collection of all FRBSU monoidal categories and the collection of all crossed modules form a 2 category.

Category Theory · Mathematics 2015-12-23 Selcan Aksoy

Categories, n-categories, double categories, and multicategories (among others) all have similar definitions as collections of cells with composition operations. We give an explicit description of the information required to define any…

Category Theory · Mathematics 2025-06-03 Brandon Shapiro

Effectful categories have two classes of morphisms: pure morphisms, which form a monoidal category; and effectful morphisms, which can only be combined monoidally with central morphisms (such as the pure ones), forming a premonoidal…

Logic in Computer Science · Computer Science 2026-03-18 Matthew Earnshaw , Chad Nester , Mario Román

A subunit in a monoidal category is a subobject of the monoidal unit for which a canonical morphism is invertible. They correspond to open subsets of a base topological space in categories such as those of sheaves or Hilbert modules. We…

Category Theory · Mathematics 2020-06-22 Pau Enrique Moliner , Chris Heunen , Sean Tull

We study the classification of submodules of module categories over monoidal categories, extending ideas of Coulembier on the classification of tensor ideals in monoidal categories. We develop a framework that applies to module categories…

Representation Theory · Mathematics 2026-03-20 Hadi Salmasian , Alistair Savage , Yaolong Shen

In this survey paper we give account of several approaches to the strictification and non-strictification of monoidal categories, which are constructions that turn a monoidal category into a (non-)strict one monoidally equivalent to the…

Category Theory · Mathematics 2024-12-31 Jorge Becerra

We study some classes of lazy cocycles, called pure (respectively neat), together with their categorical counterparts, entwined (respectively strongly entwined) monoidal categories.

Quantum Algebra · Mathematics 2008-01-16 Florin Panaite , Mihai D. Staic , Freddy Van Oystaeyen

A compact closed bicategory is a symmetric monoidal bicategory where every object is equipped with a weak dual. The unit and counit satisfy the usual "zig-zag" identities of a compact closed category only up to natural isomorphism, and the…

Category Theory · Mathematics 2016-08-22 Michael Stay

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 category theory circles it is well-known that the Schreier theory of group extensions can be understood in terms of the Grothendieck construction on indexed categories. However, it is seldom discussed how this relates to extensions of…

Category Theory · Mathematics 2023-06-28 Graham Manuell

It is well-known that the category of Kleisli algebras for a monoidal monad carries a canonical monoidal structure. We define the notion of a commutative graded monad and present a strictly two-categorical proof that Kleisli algebras for…

Category Theory · Mathematics 2022-04-05 Rowan Poklewski-Koziell

It is well known that the underlying simplicial set of any simplicial group is a Kan complex. Roughly speaking, Kan complex is an infinite-dimensional analogue of groupoid, and the relation between groupoids and categories resembles that…

Category Theory · Mathematics 2020-06-23 Ryo Horiuchi

This review paper deals with dimension theory of polynomial rings over certain families of pullbacks. While the literature is plentiful, this field is still developing and many contexts are yet to be explored. I will thus restrict the scope…

Commutative Algebra · Mathematics 2007-05-23 S. Kabbaj

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