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Related papers: Coarse and Lipschitz universality

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Main results of the paper: (1) For any finite metric space $M$ the Lipschitz free space on $M$ contains a large well-complemented subspace which is close to $\ell_1^n$. (2) Lipschitz free spaces on large classes of recursively defined…

Functional Analysis · Mathematics 2018-07-12 Stephen J. Dilworth , Denka Kutzarova , Mikhail I. Ostrovskii

We show that there exists a family of mutually singular doubling measures on Laakso space with respect to which real-valued Lipschitz functions are almost everywhere differentiable. This implies that there exists a measure zero universal…

Functional Analysis · Mathematics 2025-01-08 Sylvester Eriksson-Bique , Andrea Pinamonti , Gareth Speight

A metric space $\mathbf{X}$ is called densely complete if there exists a dense set $D$ in $\mathbf{X}$ such that every Cauchy sequence of points of $D $ converges in $\mathbf{X}$. One of the main aims of this work is to prove that the…

General Topology · Mathematics 2019-01-28 Kyriakos Keremedis , Eliza Wajch

We make a systematic study of frames for metric spaces. We prove that every separable metric space admits a metric $\mathcal{M}_d$-frame. Through Lipschitz-free Banach spaces we show that there is a correspondence between frames for metric…

Functional Analysis · Mathematics 2020-11-04 K. Mahesh Krishna , P. Sam Johnson

We introduce the notions of almost Lipschitz embeddability and nearly isometric embeddability. We prove that for $p\in [1,\infty]$, every proper subset of $L_p$ is almost Lipschitzly embeddable into a Banach space $X$ if and only if $X$…

Metric Geometry · Mathematics 2017-09-27 Florent Baudier , Gilles Lancien

We show that for every complete metric space $M$ there exists another complete metric space $N$ of the same density character such that the curve-flat quotient of $N$ is isometric to $M$. Moreover, we show that if $M$ is compact and…

Metric Geometry · Mathematics 2026-03-23 Jaan Kristjan Kaasik , Andrés Quilis

In the present paper we introduce and study the Lipschitz retractional structure of metric spaces. This topic was motivated by the analogous projectional structure of Banach spaces, a topic that has been thoroughly investigated. The more…

Functional Analysis · Mathematics 2021-06-28 Petr Hájek , Andrés Quilis

We construct a family of purely PI unrectifiable Lipschitz differentiability spaces and investigate the possible of Banach spaces targets for which Lipschitz differentiability holds. We provide a general investigation into the geometry of…

Functional Analysis · Mathematics 2025-10-30 David Bate , Pietro Wald

We consider subsets $S$ of a metric space $M$ such that Lipschitz mappings defined on $S$ can be extended to Lipschitz mappings on $M$, and we show that the union of such subsets has the same property under appropriate geometric conditions.…

Functional Analysis · Mathematics 2026-01-07 Ramón J. Aliaga , Rubén Medina

We introduce a model of the set of all Polish (=separable complete metric) spaces: the cone $\cal R$ of distance matrices, and consider geometric and probabilistic problems connected with this object. The notion of the universal distance…

Probability · Mathematics 2007-05-23 A. Vershik

For a metric space $X$, we study the space $D^{\infty}(X)$ of bounded functions on $X$ whose infinitesimal Lipschitz constant is uniformly bounded. $D^{\infty}(X)$ is compared with the space $\LIP^{\infty}(X)$ of bounded Lipschitz functions…

Metric Geometry · Mathematics 2009-01-22 E. Durand , J. A. Jaramillo

There are several characterizations of coarse embeddability of a discrete metric space into a Hilbert space. In this note we give such characterizations for general metric spaces. By applying these results to the spaces $L_p(\mu)$, we get…

Metric Geometry · Mathematics 2007-05-23 Piotr W. Nowak

We find general conditions under which Lipschitz-free spaces over metric spaces are isomorphic to their infinite direct $\ell_1$-sum and exhibit several applications. As examples of such applications we have that Lipschitz-free spaces over…

Functional Analysis · Mathematics 2021-10-08 Fernando Albiac , Jose L. Ansorena , Marek Cuth , Michal Doucha

For a fixed $K\gg 1$ and $n\in\mathbb{N}$, $n\gg 1$, we study metric spaces which admit embeddings with distortion $\le K$ into each $n$-dimensional Banach space. Classical examples include spaces embeddable into $\log n$-dimensional…

Functional Analysis · Mathematics 2016-08-10 Mikhail I. Ostrovskii , Beata Randrianantoanina

A theorem proved by Hrushovski for graphs and extended by Solecki and Vershik (independently from each other) to metric spaces leads to a stronger version of ultrahomogeneity of the infinite random graph $R$, the universal Urysohn metric…

Metric Geometry · Mathematics 2009-03-02 Vladimir G. Pestov

We show that inclusions of $p$-metric spaces always produce genuine linear embeddings at the level of Lipschitz-free $p$-spaces. More precisely, for every $0<p<1$ and every inclusion $ \mathit{N}\subset \mathit{M}$ of $p$-metric spaces, the…

Functional Analysis · Mathematics 2026-03-31 Fernando Albiac , José L. Ansorena

Enflo constructed a countable metric space that may not be uniformly embedded into any metric space of positive generalized roundness. Dranishnikov, Gong, Lafforgue and Yu modified Enflo's example to construct a locally finite metric space…

Functional Analysis · Mathematics 2019-01-17 Casey Lynn Kelleher , Daniel Miller , Trenton Osborn , Anthony Weston

We consider the problem of isometric embedding of metric spaces to the Banach spaces; and introduce and study the remarkable class of so-called linearly rigid metric spaces: these are the spaces that admit a unique, up to isometry, linearly…

Functional Analysis · Mathematics 2008-04-12 J. Melleray , F. V. Petrov , A. M. Vershik

Let (X, d) be a quasi-convex, complete and separable metric space with reference probability measure m. We prove that the set of of real valued Lipschitz function with non zero point-wise Lipschitz constant m-almost everywhere is residual,…

Analysis of PDEs · Mathematics 2013-06-21 Fabio Cavalletti

We prove that if $M$ is an infinite complete metric space then the set of strongly norm-attaining Lipschitz functions $\SA(M)$ contains a linear subspace isomorphic to $c_0$. This solves an open question posed by V. Kadets and O. Rold\'an.

Functional Analysis · Mathematics 2022-04-28 Antonio Avilés , Gonzalo Martínez-Cervantes , Abraham Rueda Zoca , Pedro Tradacete