English
Related papers

Related papers: A Full and faithful Nerve for 2-categories

200 papers

We extend the 2-representation theory of finitary 2-categories to certain 2-categories with infinitely many objects, denoted locally finitary 2-categories, and extend the classical classification results of simple transitive…

Category Theory · Mathematics 2022-01-19 James Macpherson

We associate to every divisorial (e.g. smooth) variety $X$ with only constant invertible global functions and finitely generated Picard group a $Pic(X)$-graded homogeneous coordinate ring. This generalizes the usual homogeneous coordinate…

Algebraic Geometry · Mathematics 2007-05-23 Florian Berchtold , Juergen Hausen

Let $\mathcal U$ be the 2-category associated with $\mathfrak{sl}_2$. We prove that a complex of 1-morphisms of $\mathcal U$ is null-homotopic if and only if its image in every simple 2-representation is null-homotopic. Under mild…

Representation Theory · Mathematics 2020-11-30 Laurent Vera

In this paper, we extend a result of Lafont and M{\'e}tayer and prove that the polygraphic homology of a small category, defined in terms of polygraphic resolutions in the category $\omega$Cat of strict $\omega$-categories, is naturally…

Algebraic Topology · Mathematics 2021-02-24 Léonard Guetta

This paper corrects a small mistake in a paper of Dwyer-Kan, and uses this to identify homotopy function complexes in a model category with the nerves of certain categories of zig-zags.

Algebraic Topology · Mathematics 2009-06-16 Daniel Dugger

We define a category $\mathsf{List}$ whose objects are sets and morphisms are mappings which assign to an element in the domain an ordered sequence (list) of elements in the codomain. We introduce and study a category of simplicial objects…

Algebraic Topology · Mathematics 2025-11-04 Redi Haderi , Özgün Ünlü

For a 2-category 2C we associate a notion of a principal 2C-bundle. In case of the 2-category of 2-vector spaces in the sense of M.M. Kapranov and V.A. Voevodsky this gives the the 2-vector bundles of N.A. Baas, B.I. Dundas and J. Rognes.…

Algebraic Topology · Mathematics 2008-08-01 Nils. A. Baas , Marcel Bokstedt , Tore August Kro

The main purpose of this work is the study of the homotopy theory of dg-categories up to quasi-equivalences. Our main result provides a natural description of the mapping spaces between two dg-categories $C$ and $D$ in terms of the nerve of…

Algebraic Geometry · Mathematics 2007-05-23 B. Toen

This thesis focuses on topics in 2-category theory: in particular on double categories, pseudomonads and codescent objects. In Chapter 2 we recall all the necessary notions. In Chapter 3 we show that factorization systems can be…

Category Theory · Mathematics 2025-04-08 Miloslav Štěpán

Everyone knows that if you have a bivariant homology theory satisfying a base change formula, you get an representation of a category of correspondences. For theories in which the covariant and contravariant transfer maps are in mutual…

Category Theory · Mathematics 2022-12-21 Andrew W. Macpherson

We produce a fully faithful functor from finite type nilpotent spaces to cosimplicial binomial rings, thus giving an algebraic model of integral homotopy types. As an application, we construct an integral version of the…

Algebraic Topology · Mathematics 2025-03-25 Geoffroy Horel

We extend the usual notion of parallel transport along a path to triangulated surfaces. A homotopy of paths is lifted into a fibered category with connection and this defines a functor between the fibers above the boundary paths. These…

Mathematical Physics · Physics 2007-05-23 Romain Attal

For a category B with finite products, we first characterize pseudofunctors from B to Cat whose corresponding opfibration is cartesian monoidal. Among those, we then characterize the ones which extend to pseudofunctors from internal groups…

Category Theory · Mathematics 2022-06-03 Alan S. Cigoli , Sandra Mantovani , Giuseppe Metere

In this article we analyze the structure of $2$-categories of symmetric projective bimodules over a finite dimensional algebra with respect to the action of a finite abelian group. We determine under which condition the resulting…

Representation Theory · Mathematics 2019-04-12 Volodymyr Mazorchuk , Vanessa Miemietz , Xiaoting Zhang

We make the first step towards a "nerve theorem" for graphs. Let $G$ be a simple graph and let $\mathcal{F}$ be a family of induced subgraphs of $G$ such that the intersection of any members of $\mathcal{F}$ is either empty or connected. We…

Combinatorics · Mathematics 2019-07-04 Andreas F. Holmsen , Minki Kim , Seunghun Lee

Without the axiom of choice, the free exact completion of the category of sets (i.e. the category of setoids) may not be complete or cocomplete. We will show that nevertheless, it can be enhanced to a derivator: the formal structure of…

Category Theory · Mathematics 2021-06-07 Michael Shulman

A duoidal category is a category equipped with two monoidal structures in which one is (op)lax monoidal with respect to the other. In this paper we introduce duoidal $\infty$-categories which are counterparts of duoidal categories in the…

Category Theory · Mathematics 2025-01-28 Takeshi Torii

Two of the most useful tools in topological combinatorics are the nerve lemma and discrete Morse theory. In this note we introduce a theorem that interpolates between them and allows decompositions of complexes into non-contractible pieces…

Combinatorics · Mathematics 2013-07-18 Alexander Engström

The purpose of this article is threefold: Firstly, we propose some enhancements to the existing definition of 6-functor formalisms. Secondly, we systematically study the category of kernels, which is a certain 2-category attached to every…

Category Theory · Mathematics 2024-10-18 Claudius Heyer , Lucas Mann

We construct a model structure on the category $\mathrm{DblCat}$ of double categories and double functors. Unlike previous model structures for double categories, it recovers the homotopy theory of 2-categories through the horizontal…

Algebraic Topology · Mathematics 2021-05-04 Lyne Moser , Maru Sarazola , Paula Verdugo