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Related papers: Descent for internal multicategory functors

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We define the notion of an indexed profunctor over a 2-category, and use it to develop an abstract theory of limits. The theory subsumes (conical) limits, weighted limits, ends and Kan extensions. Results include an abstract version of the…

Category Theory · Mathematics 2023-02-14 Sori Lee

In a category $\mathcal{C}$ with a proper $(\mathcal{E}, \mathcal{M})$-factorization system, we study the notions of strict, co-strict, initial and final morphisms with respect to a topogenous order. Besides showing that they allow…

Category Theory · Mathematics 2023-03-28 Minani Iragi , David Holgate

In differential geometry, the existence of pullbacks is a delicate matter, since the category of smooth manifolds does not admit all of them. When pullbacks are required, often submersions are employed as an ideal class of maps which…

Category Theory · Mathematics 2025-03-03 Geoffrey Cruttwell , Marcello Lanfranchi

Categorification is the process of finding category-theoretic analogs of set-theoretic concepts by replacing sets with categories, functions with functors, and equations between functions by natural isomorphisms between functors, which in…

Quantum Algebra · Mathematics 2014-11-18 John C. Baez , James Dolan

We develop a general theory of (extended) inner autoequivalences of objects of any 2-category, generalizing the theory of isotropy groups to the 2-categorical setting. We show how dense subcategories let one compute isotropy in the presence…

Category Theory · Mathematics 2024-05-28 Pieter Hofstra , Martti Karvonen

We consider the quotient of an exact or one-sided exact category $\mathcal{E}$ by a so-called percolating subcategory $\mathcal{A}$. For exact categories, such a quotient is constructed in two steps. Firstly, one localizes $\mathcal{E}$ at…

Category Theory · Mathematics 2020-06-22 Ruben Henrard , Adam-Christiaan van Roosmalen

Gluing of two pseudo functors has been studied by Deligne, Ayoub, and others in the construction of extraordinary direct image functors in \'etale cohomology, stable homotopy, and mixed motives of schemes. In this article, we study more…

Category Theory · Mathematics 2016-03-14 Weizhe Zheng

Neural network training is typically viewed as gradient descent on a loss surface. We propose a fundamentally different perspective: learning is a structure-preserving transformation (a functor L) between the space of network parameters…

Machine Learning · Computer Science 2025-10-07 Abdulrahman Tamim

For a given category B we are interested in studying internal categorical structures in B. This work is the starting point, where we consider reflexive graphs and precategories (i.e., for the purpose of this note, a simplicial object…

Category Theory · Mathematics 2009-03-03 N. Martins-Ferreira

We give a valuative criterion for when a smooth algebraic stack with a separated good moduli space is the quotient of a separated Deligne-Mumford stack by a torus. For doing so, we introduce a new class of morphisms, the so-called effective…

Algebraic Geometry · Mathematics 2024-01-29 Andrea Di Lorenzo , Giovanni Inchiostro

It is well-known that biological phenomena are emergent. Emergent phenomena are quite interesting and amazing. However, they are difficult to be understood. Due to this difficulty, we propose a theory to describe emergence based on a…

Category Theory · Mathematics 2018-10-30 Giuliano Gadioli La Guardia , Pedro Jeferson Miranda

Category theory unifies mathematical concepts, aiding comparisons across structures by incorporating objects and morphisms, which capture their interactions. It has influenced areas of computer science such as automata theory, functional…

Category Theory · Mathematics 2024-02-09 Nima Rasekh , Niels van der Weide , Benedikt Ahrens , Paige Randall North

We construct a machine which takes as input a locally small symmetric closed complete multicategory $\mathsf V$. And its output is again a locally small symmetric closed complete multicategory $\mathsf V\text-\mathcal{C}at$, the…

Category Theory · Mathematics 2024-10-29 Volodymyr Lyubashenko

Diagram chasing is not an easy task. The coherence holds in a generalized sense if we have a mechanical method to judge whether given two morphisms are equal to each other. A simple way to this end is to reform a concerned category into a…

Logic in Computer Science · Computer Science 2020-10-09 Ryu Hasegawa

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

Representing examples in a way that is compatible with the underlying classifier can greatly enhance the performance of a learning system. In this paper we investigate scalable techniques for inducing discriminative features by taking…

Machine Learning · Computer Science 2013-10-09 Nikos Karampatziakis , Paul Mineiro

We present an efficient and user-friendly method for constructing any cofibrantly generated model structure on the category of double categories whose trivial fibrations are the "canonical" ones: the double functors which are surjective on…

Algebraic Topology · Mathematics 2025-09-30 Lyne Moser , Maru Sarazola , Paula Verdugo

In this manuscript, we address continuous unconstrained multi-objective optimization problems and we discuss descent type methods for the reconstruction of the Pareto set. Specifically, we analyze the class of Front Descent methods, which…

Optimization and Control · Mathematics 2026-04-08 Matteo Lapucci , Pierluigi Mansueto , Davide Pucci

We study limits in 2-categories whose objects are categories with extra structure and whose morphisms are functors preserving the structure only up to a coherent comparison map, which may or may not be required to be invertible. This is…

Category Theory · Mathematics 2012-02-20 Stephen Lack , Michael Shulman

We introduce a theory for encoding and manipulating algebraic data on categories via $\textit{concentration structures}$, which are equivalence relations on morphisms that satisfy certain axioms. For any category with a concentration…

Category Theory · Mathematics 2025-10-10 Yangxiao Luo , Shunyu Wan