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Related papers: On Extension Of Functors

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The well-known difficulties arising in a classification which is not set-theoretically trivial---involving what is sometimes called a non-smooth quotient---have been overcome in a striking way in the theory of operator algebras by the use…

Operator Algebras · Mathematics 2007-11-21 George A. Elliott

Let $D$ be a large category which is cocomplete. We construct a model structure (in the sense of Quillen) on the category of small functors from $D$ to simplicial sets. As an application we construct homotopy localization functors on the…

Algebraic Topology · Mathematics 2007-05-23 Boris Chorny , William G. Dwyer

In this paper the notion of $\infty$-open-multicommutativity of functors in the category of compact Hausdorff spaces is considered. This property is a generalization of the open-multicommutativity on the case of infinite diagrams. It is…

General Topology · Mathematics 2007-05-23 Kozhan Roman

In this paper we investigate a categorical aspect of $n$-trivial extension of a ring by a family of modules. Namely, we introduce the right (resp., left) $n$-trivial extension of a category by a family of endofunctors. Among other results,…

Category Theory · Mathematics 2020-05-22 Dirar Benkhadra , Driss Bennis , J. R. Garcia Rozas

We compare two possible ways of defining a category of 1-combs, the first intensionally as coend optics and the second extensionally as a quotient by the operational behaviour of 1-combs on lower-order maps. We show that there is a full and…

Quantum Physics · Physics 2023-08-01 James Hefford , Cole Comfort

We develop a new approach of extension calculus in the category of strict polynomial functors, based on Troesch complexes. We obtain new short elementary proofs of numerous classical Ext-computations as well as new results. In particular,…

Representation Theory · Mathematics 2012-10-18 Antoine Touzé

The main result of this paper is a proof of the continuity of a family of integral functionals defined on the space of functions of bounded variation with respect to a topology under which smooth functions are dense. These functionals occur…

Analysis of PDEs · Mathematics 2014-11-24 Filip Rindler , Giles Shaw

A coextensive category can be defined as a category $\mathcal{C}$ with finite products such that for each pair $X,Y$ of objects in $\mathcal{C}$, the canonical functor $\times\colon X/\mathcal{C} \times Y/\mathcal{C} \to (X \times…

Category Theory · Mathematics 2020-08-11 David Neal Broodryk

Many branches of theoretical and applied mathematics require a quantifiable notion of complexity. One such circumstance is a topological dynamical system - which involves a continuous self-map on a metric space. There are many notions of…

Category Theory · Mathematics 2024-03-12 Suddhasattwa Das

We extend some properties of pullbacks which are known to hold in a Mal'tsev context to the more general context of Gumm categories. The varieties of universal algebras which are Gumm categories are precisely the congruence modular ones.…

Category Theory · Mathematics 2014-08-07 Marino Gran , Diana Rodelo

We review several known categorification procedures, and introduce a functorial categorification of group extensions with applications to non-abelian group cohomology. Categorification of acyclic models and of topological spaces are briefly…

Category Theory · Mathematics 2007-05-23 Lucian M. Ionescu

There is a lot of redundancy in the usual definition of adjoint functors. We define and prove the core of what is required. First we do this in the hom-enriched context. Then we do it in the cocompletion of a bicategory with respect to…

Category Theory · Mathematics 2012-01-04 Ross Street

In this paper we continue the project of generalizing tilting theory to the category of contravariant functors $Mod(C)$, from a skeletally small preadditive category $C$ to the category of abelian groups. We introduced the notion of a a…

Representation Theory · Mathematics 2015-10-02 R. Martinez-Villa , M. Ortiz-Morales

We study versions of Goodwillie's calculus of functors for indexing diagrams other than cubes. We in particular construct universal excisive approximations for a larger class of diagrams, which yields an extension of the Taylor tower. We…

Algebraic Topology · Mathematics 2025-05-08 Robin Stoll

We construct an explicit combinatorial model of the functor which adds right adjoints to the morphisms of an $\infty$-category, and we speculate on possible extensions to higher dimensions.

Category Theory · Mathematics 2025-10-08 Lorenzo Riva , Martina Rovelli

We prove that functions defined on a lattice in a finite dimensional torus with bounded finite differences can be smoothly extended to the whole torus, and relate the bounds on the extension's derivatives with bounds on the original…

Differential Geometry · Mathematics 2008-11-27 P. Duarte , M. J. Torres

Let $C$ be an additive category with cokernels and let Mod($C$) be the category of additive functors from $C^{op}$ to the category Ab of abelian groups. Let mod($C$) be the full subcategory of Mod($C$) consisting of coherent functors. In…

Category Theory · Mathematics 2020-12-16 Mohammad Khazaei , Reza Sazeedeh

We generalize Chirka's theorem on the extension of functions holomorphic in a neighbourhood of graph(F)\cup(\partial D\times D) -- where D is the open unit disc and graph(F) denotes the graph of a continuous D-valued function F -- to the…

Complex Variables · Mathematics 2007-05-23 David E. Barrett , Gautam Bharali

This paper deals with extension of analytic covers. We prove topological extension theorems for analytic covers. The main result is an extension theorem which only uses the extension of the ramification divisor. We give also a Thullen-type…

Complex Variables · Mathematics 2016-04-28 Landry Lavoine

Let L be a countable and locally finite CW complex. Suppose that the class of all metrizable compacta of extension dimension not greater than L contains a universal element which is an absolute extensor in dimension L. Our main result shows…

Geometric Topology · Mathematics 2007-05-23 Alex Karasev , Vesko Valov