English
Related papers

Related papers: Groupoidal 2-quasi-categories and homotopy 2-types

200 papers

This paper gives an introduction to the homotopy theory of quasi-categories. Weak equivalences between quasi-categories are characterized as maps which induce equivalences on a naturally defined system of groupoids. These groupoids…

Category Theory · Mathematics 2019-09-19 J. F. Jardine

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

We prove that various structures on model $\infty$-categories descend to corresponding structures on their localizations: (i) Quillen adjunctions; (ii) two-variable Quillen adjunctions; (iii) monoidal and symmetric monoidal model…

Algebraic Topology · Mathematics 2015-10-16 Aaron Mazel-Gee

We construct a category equivalent to the category $\mathbf{Mon}$ of monoids and monoid homomorphisms, based on categories with strict factorization systems. This equivalence is then extended to the category $\mathbf{Mon_s}$ of unital…

Category Theory · Mathematics 2025-10-31 Xavier Mary

Small B\'{e}nabou's bicategories and, in particular, Mac Lane's monoidal categories, have well-understood classifying spaces, which give geometric meaning to their cells. This paper contains some contributions to the study of the…

Category Theory · Mathematics 2013-09-18 M. Calvo , A. M. Cegarra , B. A. Heredia

We show that the quasicategory of frames of a cofibration category, introduced by the second-named author, is equivalent to its simplicial localization.

Algebraic Topology · Mathematics 2015-06-30 Chris Kapulkin , Karol Szumiło

We define a natural 2-categorical structure on the base category of a large class of Grothendieck fibrations. Given any model category $\mathbf{C}$, we apply this construction to a fibration whose fibers are the homotopy categories of the…

Category Theory · Mathematics 2022-02-24 Joseph Helfer

In this paper we study the homotopy theory of parameterized spectrum objects in the $\infty$-category of $(\infty, 2)$-categories, as well as the Quillen cohomology of an $(\infty, 2)$-category with coefficients in such a parameterized…

Algebraic Topology · Mathematics 2018-02-23 Yonatan Harpaz , Joost Nuiten , Matan Prasma

We show that the category of simplicial sets is a co-reflective subcategory of the category of cubical sets with connections, with the inclusion given by a version of the straightening functor. We show that using the co-reflector, one can…

Category Theory · Mathematics 2019-06-24 Chris Kapulkin , Zachery Lindsey , Liang Ze Wong

We give a complete and careful proof of Quillen's theorem on the existence of the standard model category structure on the category of topological spaces. We do not assume any familiarity with model categories.

Algebraic Topology · Mathematics 2017-10-24 Philip S. Hirschhorn

Let $D$ be a large category which is cocomplete. We construct a model structure (in the sense of Quillen) on the category of small functors from $D$ to simplicial sets. As an application we construct homotopy localization functors on the…

Algebraic Topology · Mathematics 2007-05-23 Boris Chorny , William G. Dwyer

We construct two model structures, whose fibrant objects capture the notions of discrete fibrations and of Grothendieck fibrations over a category $\mathcal{C}$. For the discrete case, we build a model structure on the slice…

Category Theory · Mathematics 2024-05-02 Lyne Moser , Maru Sarazola

This work contributes to clarifying several relationships between certain higher categorical structures and the homotopy types of their classifying spaces. Double categories (Ehresmann, 1963) have well-understood geometric realizations, and…

Algebraic Topology · Mathematics 2010-03-22 Antonio M. Cegarra , Benjamín A. Heredia , Josué Remedios

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

Working over an arbitrary field, we define compact semisimple 2-categories, and show that every compact semisimple 2-category is equivalent to the 2-category of separable module 1-categories over a finite semisimple tensor 1-category. Then,…

Quantum Algebra · Mathematics 2023-10-27 Thibault D. Décoppet

While many different models for $(\infty,1)$-categories are currently being used, it is known that they are Quillen equivalent to one another. Several higher-order analogues of them are being developed as models for $(\infty,…

Algebraic Topology · Mathematics 2016-01-20 Julia E. Bergner , Charles Rezk

We construct a theory of 2-vector bundles over a Lie groupoid, with fibers modeled by the bicategory of super algebras, bimodules and intertwiners. We demonstrate that these 2-vector bundles form a symmetric monoidal 2-stack. From this…

Algebraic Topology · Mathematics 2026-01-23 Zhen Huan

We define the notion of a multi-sorted algebraic theory, which is a generalization of an algebraic theory in which the objects are of different "sorts." We prove a rigidification result for simplicial algebras over these theories, showing…

Algebraic Topology · Mathematics 2009-05-26 Julia E Bergner

We define locally wide finitary 2-categories by relaxing the definition of finitary 2-categories to allow infinitely many objects and isomorphism classes of 1-morphisms and infinite dimensional hom-spaces of 2-morphisms. After defining…

Category Theory · Mathematics 2021-06-24 James Macpherson

We give a new construction of the model structure on the category of simplicial sets for homotopy $n$-types, originally due to Elvira-Donazar and Hernandez-Paricio, using a right transfer along the coskeleton functor. We observe that an…

Category Theory · Mathematics 2025-12-23 Chris Kapulkin , Udit Mavinkurve