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Related papers: Functors Preserving Effective Descent Morphisms

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We investigate the properties of lax comma categories over a base category $X$, focusing on topologicity, extensivity, cartesian closedness, and descent. We establish that the forgetful functor from $\mathsf{Cat}//X$ to $\mathsf{Cat}$ is…

Category Theory · Mathematics 2024-06-13 Maria Manuel Clementino , Fernando Lucatelli Nunes , Rui Prezado

We present a characterization of effective descent morphisms in the lax comma category $\mathsf{Ord}//X$ when $X$ is a locally complete ordered set, as well as in the antisymmetric setting.

Category Theory · Mathematics 2025-03-21 Maria Manuel Clementino , Rui Prezado

This article studies descent theory in the setting of Berkovich spaces. We give sufficient conditions for a given fibered category over the category of k-affinoid algebras to be a stack for the Berkovich analogue of the faithfully-flat…

Algebraic Geometry · Mathematics 2023-01-11 Mathieu Daylies

We initiate the study of deformation theory in the context of derived and higher log geometry. After reconceptualizing the "exactification"-procedures in ordinary log geometry in terms of Quillen's approach to the cotangent complex, we…

Algebraic Topology · Mathematics 2025-06-25 Tommy Lundemo

Tangent categories are categories equipped with a tangent functor: an endofunctor with certain natural transformations which make it behave like the tangent bundle functor on the category of smooth manifolds. They provide an abstract…

Category Theory · Mathematics 2017-03-10 J. R. B. Cockett , G. S. H. Cruttwell

We prove a version of Grothendieck's descent theorem on an `enriched' principal fiber bundle, a principal fiber bundle with an action of a larger group scheme. Using this, we prove the isomorphisms of the equivariant Picard and the class…

Commutative Algebra · Mathematics 2014-03-20 Mitsuyasu Hashimoto

Effective field theories (EFTs) provide a powerful framework to parametrise unknown aspects of possible ultraviolet (UV) physics. For scalar fields in de Sitter space, however, new emergent phenomena can arise when the cut-off scale of the…

High Energy Physics - Theory · Physics 2025-11-06 Sebastian Cespedes , Zhehan Qin , Dong-Gang Wang

The description of algebraic structure of n-fold loop spaces can be done either using the formalism of topological operads, or using variations of Segal's $\Gamma$-spaces. The formalism of topological operads generalises well to different…

Category Theory · Mathematics 2017-01-31 Edouard Balzin

This paper studies fundamental questions concerning category-theoretic models of induction and recursion. We are concerned with the relationship between well-founded and recursive coalgebras for an endofunctor. For monomorphism preserving…

Logic in Computer Science · Computer Science 2020-02-18 Jiří Adámek , Stefan Milius , Lawrence S. Moss

Consider a cofibrantly generated model category $S$, a small category $C$ and a subcategory $D$ of $C$. We endow the category $S^C$ of functors from $C$ to $S$ with a model structure, defining weak equivalences and fibrations objectwise but…

K-Theory and Homology · Mathematics 2007-05-23 Paul Balmer , Michel Matthey

We study a condensed version of the \'etale homotopy type of a scheme, which refines both the usual \'etale homotopy type of Friedlander-Artin-Mazur and the pro\'etale fundamental group of Bhatt-Scholze. In the first part of this paper, we…

We study the notion of fundamental group in the framework of descent-exact homological categories. This setting is sufficiently wide to include several categories of "algebraic" nature such as the almost abelian categories, the semi-abelian…

Category Theory · Mathematics 2016-04-13 Mathieu Duckerts-Antoine

Any modality in homotopy type theory gives rise to an orthogonal factorization system of which the left class is stable under pullbacks. We show that there is a second orthogonal factorization system associated to any modality, of which the…

Category Theory · Mathematics 2020-10-28 Felix Cherubini , Egbert Rijke

In this paper, we consider some variations on Mann's definition $\infty$-categorical definition of abstract six-functor formalisms. We consider Nagata six-functor formalisms, that have the additional requirement of having Grothendieck and…

Algebraic Geometry · Mathematics 2026-04-10 Josefien Kuijper

We systematically investigate morphisms and equivalences of toposes from multiple points of view. We establish a dual adjunction between morphisms and comorphisms of sites, introduce the notion of weak morphism of toposes and characterize…

Category Theory · Mathematics 2020-08-04 Olivia Caramello

For any suitable base category $\mathcal{V} $, we find that $\mathcal{V} $-fully faithful lax epimorphisms in $\mathcal{V} $-$\mathsf{Cat} $ are precisely those $\mathcal{V}$-functors $F \colon \mathcal{A} \to \mathcal{B}$ whose induced…

Category Theory · Mathematics 2023-11-13 Fernando Lucatelli Nunes , Rui Prezado , Lurdes Sousa

Shape-constrained functional data encompass a wide array of application fields, such as activity profiling, growth curves, healthcare and mortality. Most existing methods for general functional data analysis often ignore that such data are…

Methodology · Statistics 2024-08-13 Poorbita Kundu , Hans-Georg Müller

Given a functor $p:E \rightarrow B$ and an object $e \in E$ , we define a \emph{displacement} of $e$ along a morphism $\varepsilon: p(e) \rightarrow b$, as a map $e \rightarrow \nabla_\varepsilon(e)$ satisfying a universal property analogue…

Category Theory · Mathematics 2014-07-10 Hugo V. Bacard

Fractional derivatives are a well-studied generalization of integer order derivatives. Naturally, for optimization, it is of interest to understand the convergence properties of gradient descent using fractional derivatives. Convergence…

Optimization and Control · Mathematics 2024-06-05 Ashwani Aggarwal

We develop some aspects of the theory of derivators, pointed derivators, and stable derivators. As a main result, we show that the values of a stable derivator can be canonically endowed with the structure of a triangulated category.…

Algebraic Topology · Mathematics 2014-10-01 Moritz Groth