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Related papers: Positive definite metric spaces

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In this article, the author proposes another way to define the completion of a metric space, which is different from the classical one via the dense property, and prove the equivalence between two definitions. This definition is based on…

Functional Analysis · Mathematics 2011-12-06 Cheng Hao

We show that there are uncountably many mutually non-isomorphic Lipschitz-free spaces over countable, complete, discrete metric spaces. Also there is a countable, complete, discrete metric space whose free space does not embed into the free…

Functional Analysis · Mathematics 2025-05-27 Estelle Basset , Gilles Lancien , Antonín Procházka

With a simple generic approach, we develop a classification that encodes and measures the strength of completeness (or compactness) properties in various types of spaces and ordered structures. The approach also allows us to encode notions…

General Topology · Mathematics 2020-12-01 Hanna Ćmiel , Franz-Viktor Kuhlmann , Katarzyna Kuhlmann

This paper is concerned with the construction of positive definite functions on a cartesian product of quasi-metric spaces using generalized Stieltjes and complete Bernstein functions. The results we prove are aligned with a…

Classical Analysis and ODEs · Mathematics 2020-11-20 Victor S. Barbosa , Valdir A. Menegatto

Quantifying the distance between datasets is a fundamental question in mathematics and machine learning. We propose \textit{magnitude distance}, a novel distance metric defined on finite datasets using the notion of the \emph{magnitude} of…

Machine Learning · Computer Science 2026-02-10 Sahel Torkamani , Henry Gouk , Rik Sarkar

Characterisations of metrizable topological spaces or metrizable uniform spaces are well known. A natural counterpart to being metrizable for topological spaces can be expressed in terms of probabilistic metrizability for approach spaces.…

General Topology · Mathematics 2026-01-13 Eva Colebunders , Robert Lowen

Magnitude homology is an $\mathbf{R}^+$-graded homology theory of metric spaces that captures information on the complexity of geodesics. Here we address the question: when are two metric spaces magnitude homology equivalent, in the sense…

Metric Geometry · Mathematics 2026-02-25 Adrián Doña Mateo , Tom Leinster

A metric space is said to be strongly rigid if no positive distance is taken twice by the metric. In 1972, Janos proved that a separable metrizable space has a strongly rigid metric if and only if it is zero-dimensional. In this paper, we…

Metric Geometry · Mathematics 2026-01-13 Yoshito Ishiki

Similarity metric which is not positive definite, and present a general theorem which provides a large family of similarity metrics which are positive definite.

Functional Analysis · Mathematics 2023-07-21 Daniel Alpay , Liora Mayats-Alpay

Magnitude homology was introduced by Hepworth and Willerton in the case of graphs, and was later extended by Leinster and Shulman to metric spaces and enriched categories. Here we introduce the dual theory, magnitude cohomology, which we…

Algebraic Topology · Mathematics 2022-04-25 Richard Hepworth

A new method of metric space investigation, based on classification of its finite subspaces, is suggested. It admits to derive information on metric space properties which is encoded in metric. The method describes geometry in terms of only…

Metric Geometry · Mathematics 2007-05-23 Yuri A. Rylov

In this paper we introduce the concept of the rectangular metric like spaces, along with its topology and we prove some fixed point theorems under different contraction principles. We introduce the concept of modified metric-like space as…

General Topology · Mathematics 2018-03-16 Nabil Mlaiki , Kamal Abudayeh , Thabet Abdeljawad , Muhib Abuloha

Schanuel has pointed out that there are mathematically interesting categories whose relationship to the ring of integers is analogous to the relationship between the category of finite sets and the semi-ring of non-negative integers. Such…

Combinatorics · Mathematics 2007-05-23 James Propp

We characterize $n$-rectifiable metric measure spaces as those spaces that admit a countable Borel decomposition so that each piece has positive and finite $n$-densities and one of the following: is an $n$-dimensional Lipschitz…

Metric Geometry · Mathematics 2018-09-18 David Bate , Sean Li

In this paper the notion of modular cone metric space is introduced and some properties of such spaces are investigated. Also we define convex modular cone metric which takes values in CR(Y) where Y is a compact Hausdorff space. Then a…

Functional Analysis · Mathematics 2013-10-15 Saeedeh Shamsi Gamchi , Mohammad Janfada , Asadollah Niknam

Let $T$ be a compact, metrisable and strongly countable-dimensional topological space. Let $\mathcal{M}^T$ be the set of all metrics $d$ on $T$ compatible with its topology, and equip $\mathcal{M}^T$ with the topology of uniform…

Functional Analysis · Mathematics 2024-05-31 Filip Talimdjioski

A compactness of the Revuz map is established in the sense that the locally uniform convergence of a sequence of positive continuous additive functionals is derived in terms of their smooth measures. To this end, we first introduce a metric…

Probability · Mathematics 2024-05-08 Yasuhito Nishimori , Matsuyo Tomisaki , Kaneharu Tsuchida , Toshihiro Uemura

The magnitude of finite categories is a generalization of the Euler characteristic. It is defined using the coarse incidence algebra of rational-valued functions on the given finite category, and a distinguished element in this algebra: the…

Category Theory · Mathematics 2023-12-14 Stephanie Chen , Juan Pablo Vigneaux

The topological entropy of a continuous self-map of a compact metric space can be defined in several distinct ways; when the space is not assumed compact, these definitions can lead to distinct invariants. The original, purely topological…

Dynamical Systems · Mathematics 2007-05-23 Boris Hasselblatt , Zbigniew Nitecki , James Propp

A finitely-additive measure $\lambda $ on an infinite-dimensional real Hilbert space $E$ which is invariant with respect to shifts and orthogonal mappings has been defined. This measure can be considered as the analog of the Lebesgue…

Functional Analysis · Mathematics 2021-09-28 Vsevolod Sakbaev