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Related papers: Reflections and Sheafifications in Algebraic and T…

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We outline the theory of reflections for prederivators, derivators and stable derivators. In order to parallel the classical theory valid for categories, we outline how reflections can be equivalently described as categories of fractions,…

Category Theory · Mathematics 2018-02-23 Fosco Loregian

Let $\mathbb{D}$ be the category of pro-sets (or abelian pro-groups). It is proved that for any Grothendieck site $X$, there exists a reflector from the category of precosheaves on $X$ with values in $\mathbb{D}$ to the full subcategory of…

Algebraic Topology · Mathematics 2016-05-06 Andrei V. Prasolov

We develop a theory of residues for arithmetic surfaces, establish the reciprocity law around a point, and use the residue maps to explicitly construct the dualizing sheaf of the surface. These are generalisations of known results for…

Number Theory · Mathematics 2011-01-17 Matthew Morrow

Firstly, precise conditions on how to obtain very-well-behaved epireflections are explored and improved from the author's previous papers; meaning that, beginning with a monad and a prefactorization system on a category, is produced a…

Category Theory · Mathematics 2025-09-10 João J. Xarez

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

Our aim is to give some insights about how to approach the formal description of situations where one has to conciliate several contradictory statements, rules, laws or ideas. We show that such a conciliation structure can be naturally…

Logic · Mathematics 2011-07-04 Dominique Lambert , Bertrand Hespel

In this paper, we provide a direct approach to $\mathbf{K}$-reflections of $T_0$ spaces. For a full subcategory $\mathbf{K}$ of the category of all $T_0$ spaces and a $T_0$ space $X$, let $\mathbf{K}(X)=\{A\subseteq X : A$ is closed and for…

General Topology · Mathematics 2019-11-27 Xiaoquan Xu

We give a necessary and sufficient condition, in terms of a certain reflection principle, for every unconditionally closed subset of a group G to be algebraic. As a corollary, we prove that this is always the case when G is a direct product…

Group Theory · Mathematics 2009-04-07 Dikran Dikranjan , Dmitri Shakhmatov

We study the cluster category of a canonical algebra A in terms of the hereditary category of coherent sheaves over the corresponding weighted projective line X. As an application we determine the automorphism group of the cluster category…

Representation Theory · Mathematics 2020-09-28 Michael Barot , Dirk Kussin , Helmut Lenzing

A semi-localization of a category is a full reflective subcategory with the property that the reflector is semi-left-exact. In this article we first determine an abstract characterization of the categories which are semi-localizations of an…

Category Theory · Mathematics 2016-02-09 Marino Gran , Stephen Lack

We introduce an original notion of extra-fine sheaf on a topological space, and a variant (hyper-extra-fine) for which \v{C}ech cohomology in strictly positive degree vanishes. We provide a characterization of such sheaves when the…

Algebraic Topology · Mathematics 2020-12-21 Daniel Bennequin , Olivier Peltre , Grégoire Sergeant-Perthuis , Juan Pablo Vigneaux

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 describe an analogue of the notion of a perverse sheaf in the setting of the derived category of coherent sheaves on an algebraic stack. Under strong additional assumptions the construction of coherent "intersection cohomology" complexes…

Algebraic Geometry · Mathematics 2021-02-04 Dmitry Arinkin , Roman Bezrukavnikov

We define and investigate a sheaf of modules on the prime spectra of modules and it is shown that there is an isomorphism between the sections of this sheaf and the ideal transform module.

Commutative Algebra · Mathematics 2013-05-08 D. Hassanzadeh-Lelekaami , H. Roshan-Shekalgourabi

Let $C$ be a completely algebraic closed non-archimedean field over $\mathbb{Q}_p$ and $\alpha,r$ be two positive integers. Denote by $B_\alpha$ the ring $\mathbb{B}_{\mathrm{dR}}^+(C)/(\ker\theta)^\alpha$. This paper first constructs a…

Algebraic Geometry · Mathematics 2026-01-13 Jiahong Yu

Let $K$ be a local field, $X$ the Drinfel'd symmetric space $X$ of dimension $d$ over $K$ and ${\mathfrak X}$ the natural formal ${\mathcal O}_K$-scheme underlying $X$; thus $G={\rm GL}\sb {d+1}(K)$ acts on $X$ and ${\mathfrak X}$. Given a…

Algebraic Geometry · Mathematics 2014-08-15 Elmar Grosse-Klönne

In this paper, we investigate the properties of $A$-coherent and $A$-quasi-coherent sheaves within the framework of algebraic geometry over non-algebraically closed fields. We define an $\mathcal{O}_X$-module to be $A$-coherent (resp.…

Algebraic Geometry · Mathematics 2026-04-20 Hamet Seydi , Teylama Miabey

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

We model problems as presheaves that assign sets of certificates to input instances, and we show how to use presheaf \v{C}ech cohomology to capture the precise ways in which local solutions fail to patch into global ones. Applied to…

Commutative Algebra · Mathematics 2025-11-03 Anny Beatriz Azevedo , Benjamin Merlin Bumpus , Matteo Capucci , James Fairbanks , Daniel Rosiak

Our work is motivated by obtaining solutions to the quantum reflection equation (qRE) by categorical methods. To start, given a braided monoidal category $\mathcal{C}$ and $\mathcal{C}$-module category $\mathcal{M}$, we introduce a version…

Quantum Algebra · Mathematics 2025-06-18 Robert Laugwitz , Chelsea Walton , Milen Yakimov