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Related papers: Some Ideas on Categories and Sheaves

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In these self-contained low prerequisite introductory notes we first present (in part 1) basic concepts of set theory and algebra without explicit category theory. We then present (in part 2) basic category theory involving a somewhat…

Category Theory · Mathematics 2021-01-07 Earnest Akofor

We introduce and develop the theory of metric sheaves. A metric sheaf $\A$ is defined on a topological space $X$ such that each fiber is a metric model. We describe the construction of the generic model as the quotient space of the sheaf…

Logic · Mathematics 2012-04-06 Maicol A. Ochoa , Andrés Villaveces

In this article, the theory of sheaves is studied from a categorical point of view. This perspective vastly generalizes the usual theory of sheaves of sets to a more abstract setting which allows us to investigate the theory of sheaves with…

Commutative Algebra · Mathematics 2017-09-22 Abolfazl Tarizadeh

We study the homotopy theory of locally ordered spaces, that is manifolds with boundary whose charts are partially ordered in a compatible way. Their category is not particularly well-behaved with respect to colimits. However, this category…

Algebraic Topology · Mathematics 2009-12-21 Krzysztof Worytkiewicz

In [1] we introduced the concept of structured space, which is a topological space that locally resembles some algebraic structures. In [2] we proceeded the study of these spaces, developing two cohomology theories. The aim of this paper is…

Algebraic Topology · Mathematics 2020-04-28 Manuel Norman

We introduce the notion of a "graded topological space": a topological space endowed with a sheaf of abelian groups which we think of as a sheaf of gradings. Any object living on a graded topological space will be graded by this sheaf of…

Algebraic Geometry · Mathematics 2020-07-20 Clemens Koppensteiner

This paper is the first in a series of papers in which we define and study a category of "sheaves of $\mathcal Z$-modules on the set of alcoves" that carries important information on the category of representations of semisimple Lie…

Representation Theory · Mathematics 2017-01-16 Peter Fiebig , Martina Lanini

Essentials of sheaves are briefly presented, followed by related comments on presheaves, bundles, manifolds and singularities, aiming to point to their differences not only in their different formal mathematical structures, but also in the…

General Mathematics · Mathematics 2009-07-07 Elemer E Rosinger

The aim of this paper is to give a unifying description of various constructions (subanalytic, semialgebraic, o-minimal site) using the notion of T-topology. We then study the category of T-sheaves.

Algebraic Geometry · Mathematics 2016-09-02 Mario J. Edmundo , Luca Prelli

We develop sheaf theory in the context of difference algebraic geometry. We introduce categories of difference sheaves and develop the appropriate cohomology theories. As specializations, we get difference Galois cohomology, difference…

Algebraic Geometry · Mathematics 2020-07-10 Marcin Chałupnik , Piotr Kowalski

We introduce a topology on the space of all isomorphism types represented in a given class of countable models, and use this topology as an aid in classifying the isomorphism types. This mixes ideas from effective descriptive set theory and…

Logic · Mathematics 2019-08-20 Russell Miller

We provide a formal introduction into the classic theorems of general topology and its axiomatic foundations in set theory. In this second part we introduce the fundamental concepts of topological spaces, convergence, and continuity, as…

History and Overview · Mathematics 2013-07-01 Felix Nagel

We define a notion on preadditive categories which plays a role similar to the notion of a Grothendieck pretopology on an unenriched category. Each such additive pretopology defines an additive Grothendieck topology and suffices to define…

Category Theory · Mathematics 2022-10-18 Kevin Coulembier

This is the third installment in a series of papers on algebraic set theory. In it, we develop a uniform approach to sheaf models of constructive set theories based on ideas from categorical logic. The key notion is that of a "predicative…

Logic · Mathematics 2014-02-26 Benno van den Berg , Ieke Moerdijk

This document develops general concepts useful for extracting knowledge embedded in large graphs or datasets that have pair-wise relationships, such as cause-effect-type relations. Almost no underlying assumptions are made, other than that…

Machine Learning · Computer Science 2019-02-22 Linas Vepstas

We extend the theory of fields/distributions developed the paper "A Feigin-Frenkel theorem with n singularities" to a general base scheme. In order to do so we introduce suitable notions of topological sheaves on schemes and study their…

Algebraic Geometry · Mathematics 2025-09-30 Luca Casarin , Andrea Maffei

There is an interplay between models, specified by variables and equations, and their connections to one another. This dichotomy should be reflected in the abstract as well. Without referring to the models directly -- only that a model…

Algebraic Topology · Mathematics 2016-11-04 Michael Robinson

A quick overview of category theory and topos theory including slice categories, monics, epics, isos, diagrams, cones, cocones, limits, colimits, products and coproducts, pushouts and pullbacks, equalizers and coequalizers, initial and…

Category Theory · Mathematics 2024-07-01 Eric Schmid

Given a general finite group $G$, we consider several categories built on it, their Grothendieck topologies and resulting sheaf categories. For a certain class of transporter categories and their quotients, equipped with atomic topology, we…

Representation Theory · Mathematics 2022-03-10 Tengfei Xiong , Fei Xu

We initiate the study of sheaves on Cech closure spaces, providing a new, unified approach to sheaf theory on many of the major classes of spaces of interest to applications: topological spaces, finite simplicial complexes (seen as $T_0$…

Algebraic Topology · Mathematics 2025-10-21 Antonio Rieser
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