English
Related papers

Related papers: Characterizations of John spaces

200 papers

In this paper we have obtained two more characterizations of nearly pseudocompact spaces.

General Topology · Mathematics 2022-03-28 Biswajit Mitra , Sanjib Das

We study a family of inequalities on pairs of measure spaces involving functions defined on product domains. Our main result establishes a Jensen-type inequality under a general product-measure framework, extending classical inequalities…

Functional Analysis · Mathematics 2026-03-09 P. D. Johnson , R. N. Mohapatra , Shankhadeep Mondal

The Urysohn universal metric space U is characterized up to isometry by the following properties: (1) U is complete and separable; (2) U contains an isometric copy of every separable metric space; (3) every isometry between two finite…

General Topology · Mathematics 2021-08-27 Vladimir Uspenskij

Although the hyperbolic metric possesses many remarkable properties, it is not defined on arbitrary subdomains of $\mathbb{R}^n$ with $n \geq 2$. This article introduces a new hyperbolic-type metric that provides an alternative approach to…

Metric Geometry · Mathematics 2025-08-01 Bibekananda Maji , Pritam Naskar , Swadesh Kumar Sahoo

We show that the sequence of dimensions of the linear spaces, generated by a given rank-metric code together with itself under several applications of a field automorphism, is an invariant for the whole equivalence class of the code. These…

Information Theory · Computer Science 2019-05-28 Alessandro Neri , Sven Puchinger , Anna-Lena Horlemann-Trautmann

We characterize symmetric spaces without focal points by the equality case of general equalities between geometric quantities.

Differential Geometry · Mathematics 2017-11-09 François Ledrappier , Lin Shu

We construct a universal space for the class of proper metric spaces of bounded geometry and of given asymptotic dimension. As a consequence of this result, we establish coincidence of the asymptotic dimension with the asymptotic inductive…

Geometric Topology · Mathematics 2007-05-23 A. Dranishnikov , M. Zarichnyi

The purpose of this article is to characterize the quasi-isometry type of a proper metric space via the Banach algebra of Higson functions on it.

Metric Geometry · Mathematics 2013-11-15 Jesús A. Álvarez López , Alberto Candel

In this paper we present a new characterization of Sobolev spaces on Euclidian spaces ($\mathbb{R}^n$). Our characterizing condition is obtained via a quadratic multiscale expression which exploits the particular symmetry properties of…

Classical Analysis and ODEs · Mathematics 2010-11-30 Roc Alabern , Joan Mateu , Joan Verdera

We present a complete system of inequalities for the inradius, circumradius, and diameter in the $3$-dimensional Euclidean space. To do so, we prove quasiconcavity of the inradius evaluated over $n$-simplices with a common facet…

Metric Geometry · Mathematics 2025-09-08 René Brandenberg , Bernardo González Merino , Mia Runge

We study the way in which the Euclidean subspaces of a Banach space fit together, somewhat in the spirit of the Ka\v{s}in decomposition. The main tool that we introduce is an estimate regarding the convex hull of a convex body in John's…

Functional Analysis · Mathematics 2015-05-06 Daniel J. Fresen

Most research into similarity search in metric spaces relies upon the triangle inequality property. This property allows the space to be arranged according to relative distances to avoid searching some subspaces. We show that many common…

Information Retrieval · Computer Science 2017-03-03 Richard Connor , Franco Alberto Cardillo , Lucia Vadicamo , Fausto Rabitti

In this article, we continue our investigations of the boundary behavior of harmonic mappings. We first discuss the classical problem on the growth of radial length and obtain a sharp growth theorem of the radial length of…

Complex Variables · Mathematics 2017-01-27 Shaolin Chen , Saminathan Ponnusamy

The main results of this paper show that various coarse (`large scale') geometric properties are closely related. In particular, we show that property A implies the operator norm localisation property, and thus that norms of operators…

Metric Geometry · Mathematics 2012-03-29 Jacek Brodzki , Graham A. Niblo , Jan Spakula , Rufus Willett , Nick J. Wright

We study the isoperimetric problem in product spaces equipped with the uniform distance. Our main result is a characterization of isoperimetric inequalities which, when satisfied on a space, are still valid for the product spaces, up a to a…

Functional Analysis · Mathematics 2014-11-14 Franck Barthe , Benoit Huou

The main aim of this paper is to give a complete solution to one of the open problems, raised by Heinonen from 1989, concerning the subinvariance of John domains under quasiconformal mappings in $\IR^n$. As application, the quasisymmetry of…

Complex Variables · Mathematics 2013-07-22 M. Huang , Y. Li , S. Ponnusamy , X. Wang

We introduce and discuss a multivariate version of the classical median that is based on an equipartition property with respect to quarter spaces. These arise as pairwise intersections of the half-spaces associated with the coordinate…

Statistics Theory · Mathematics 2022-06-24 Ludwig Baringhaus , Rudolf Grübel

The main aim of the paper is to give a full classification (up to isometry) of all metric spaces X with the following two properties: X contains a compact set with non-empty interior; and for any three distinct points a, b and c of X there…

Metric Geometry · Mathematics 2025-01-08 Piotr Niemiec

The essence of the notion of lineability and spaceability is to find linear structures in somewhat chaotic environments. The existing methods, in general, use \textit{ad hoc} arguments and few general techniques are known. Motivated by the…

Functional Analysis · Mathematics 2015-10-01 Tony K. Nogueira , Daniel Pellegrino

We determine when a quasi-isometry between discrete spaces is at bounded distance from a bilipschitz map. From this we prove a geometric version of the Von Neumann conjecture on amenability. We also get some examples in geometric groups…

Group Theory · Mathematics 2009-09-25 Kevin Whyte