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Many of the properties of sectional category, topological complexity and homotopic distance are in fact derived from a small number of basic properties, which, once established, lead to all the others without further recourse to topology.…

Algebraic Topology · Mathematics 2025-08-26 Jean-Paul Doeraene , Mohammed El Haouari

In this text we expose basic cases of some fundamental ideas and methods of topology. Namely, of homotopy, degree, fundamental group, covering, Whitehead invariant, etc. This is done by considering the elementary example: closed polygonal…

History and Overview · Mathematics 2026-05-07 E. Alkin , O. Nikitenko , A. Skopenkov

Topological transforms have been very useful in statistical analysis of shapes or surfaces without restrictions that the shapes are diffeomorphic and requiring the estimation of correspondence maps. In this paper we introduce two…

Algebraic Topology · Mathematics 2023-06-27 Henry Kirveslahti , Sayan Mukherjee

A notion of general manifolds is introduced. It covers all usual manifolds in mathematics. Essentially, it is a way how to get a bigger 'fibration' over a site which locally coincides with a given one. An enrichment with generalized…

Category Theory · Mathematics 2007-05-23 G. V. Kondratiev

Functions with uniform sublevel sets can represent orders, preference relations or other binary relations and thus turn out to be a tool for scalarization that can be used in multicriteria optimization, decision theory, mathematical…

Optimization and Control · Mathematics 2017-12-06 Petra Weidner

Urysohn constructed a separable complete universal metric space homogeneous for all finite subspaces, which is today called the Urysohn universal metric space. Some authors have recently investigated an ultrametric analogue of this space.…

Metric Geometry · Mathematics 2023-06-27 Yoshito Ishiki

Spatial understanding is a fundamental problem with wide-reaching real-world applications. The representation of spatial knowledge is often modeled with spatial templates, i.e., regions of acceptability of two objects under an explicit…

Artificial Intelligence · Computer Science 2020-03-09 Guillem Collell , Luc Van Gool , Marie-Francine Moens

Here we classify all topological spaces where all bijections to itself are homeomorphisms. As a consequence, we also classify all topological spaces where all maps to itself are continuous. Analogously, we classify all measurable spaces…

General Topology · Mathematics 2024-01-10 Lucas H. R. de Souza

Any procedure applied to data, and any quantity derived from data, is required to respect the nature and symmetries of the data. This axiom applies to refinement procedures and multiresolution transforms as well as to more basic operations…

Numerical Analysis · Mathematics 2019-07-18 Johannes Wallner

We consider Schmidt's game on the space of compact subsets of a given metric space equipped with the Hausdorff metric, and the space of continuous functions equipped with the supremum norm. We are interested in determining the generic…

Metric Geometry · Mathematics 2021-03-26 Ábel Farkas , Jonathan M. Fraser , Erez Nesharim , David Simmons

We characterize the uniform convergence points set of a pointwisely convergent sequence of real-valued functions defined on a perfectly normal space. We prove that if $X$ is a perfectly normal space which can be covered by a disjoint…

General Topology · Mathematics 2020-08-12 Olena Karlova

This article aims at finding sufficient conditions for a family of meromorphic functions to be normal by involving partial sharing of sets with differential polynomials. Moreover, corresponding results for normal meromorphic functions are…

Complex Variables · Mathematics 2025-10-24 Kuldeep Singh Charak , Nikhil Bharti , Anil Singh

This paper investigates spaces equipped with a family of metric-like functions satisfying certain axioms. These functions provide a unified framework for defining topology, uniformity, and diffeology. The framework is based on a family of…

General Topology · Mathematics 2026-03-25 Masaki Taho

Whether the goal is to analyze voting behavior, locate facilities, or recommend products, the problem of translating between (ordinal) rankings and (numerical) utilities arises naturally in many contexts. This task is commonly approached by…

Theoretical Economics · Economics 2026-02-03 Joshua Zeitlin , Corinna Coupette

Many interesting classes of maps from homotopical algebra can be characterised as those maps with the right lifting property against certain sets of maps (such classes are sometimes referred to as cofibrantly generated). In a more…

Category Theory · Mathematics 2018-02-20 Andrew Swan

It is shown that Nobeling spaces are uniquely determined by the universal extension and embedding properties.

Geometric Topology · Mathematics 2007-05-23 Michael Levin

To study problems involving heights as, eg, Manin's conjecture on the number of points of bounded height on an algebraic variety defined over a number field, it is desirable to have a good normalization of these height functions. We show…

Algebraic Geometry · Mathematics 2007-05-23 Antoine Chambert-Loir , Yuri Tschinkel

Hardy spaces in the complex plane and in higher dimensions have natural finite-dimensional subspaces formed by polynomials or by linear maps. We use the restriction of Hardy norms to such subspaces to describe the set of possible…

Complex Variables · Mathematics 2020-03-24 Leonid V. Kovalev , Xuerui Yang

We show that if there exists a topologically expansive homeomorphism on a uniform space, then the space is always a regular space. Through examples we show that in general composition of topologically expansive homeomorphisms need not be…

Dynamical Systems · Mathematics 2019-03-26 Ali Barzanouni , Ekta Shah

We define the universal exponential extension of an algebraically closed differential field and investigate its properties in the presence of a nice valuation and in connection with linear differential equations. Next we prove normalization…

Commutative Algebra · Mathematics 2026-04-28 Matthias Aschenbrenner , Lou van den Dries , Joris van der Hoeven