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Related papers: Characterization of Fr\'{e}chet Spaces and Applica…

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We consider approximations of a continuous function on a countable normed Fr\'{e}chet space by analytic and $*$-analytic. Also we found a criterium of the existence of an extension of a continuous function from a dense subspace of a…

Functional Analysis · Mathematics 2015-05-01 M. A. Mytrofanov , A. V. Ravsky

In the present paper, the Lindelof number and the degree of compactness of spaces and of the cozero-dimensional kernel of paracompact spaces are characterized in terms of selections of lower semi-continuous closed-valued mappings into…

General Topology · Mathematics 2009-03-23 Mitrofan M. Choban , Ekaterina P. Mihaylova , Stoyan I. Nedev

We consider the problem of estimating the Fr\'echet and conditional Fr\'echet mean from data taking values in separable metric spaces. Unlike Euclidean spaces, where well-established methods are available, there is no practical estimator…

Statistics Theory · Mathematics 2026-02-06 László Györfi , Pierre Humbert , Batiste Le Bars

In this manuscript, we claim that the newly introduced $\mathcal{F}$-metric space \cite[\, M.~Jleli and B.~Samet, On a new generalization of metric spaces, J. Fixed Point Theory Appl, 20(3) 2018]{JS1} is metrizable. Also, we deduce that the…

Functional Analysis · Mathematics 2018-08-09 Sumit Som , Ashis Bera , Lakshmi Kanta Dey

We discuss a method to estimate the measure of a compact set which is approximated using the Hausdorff distance by a sequence of compact sets. We do this by considering corresponding fattenings of the sequence of compact sets and showing…

Spectral Theory · Mathematics 2025-12-01 Lior Tenenbaum

The aim of the paper is to introduce the spaces $\ell_{\infty}^{\lambda}(\widehat{F})$ and $\ell_{p}^{\lambda}(\widehat{F})$ derived by the composition of the two infinite matrices $\Lambda=(\lambda_{nk})$ and $\widehat{F}=\left( f_{nk}…

Functional Analysis · Mathematics 2017-06-23 Anupam Das , Bipan Hazarika , Feyzi Başar

In the main result of the paper we extend Rosenthal's characterization of Banach spaces with the Schur property by showing that for a quasi-complete locally convex space $E$ whose separable bounded sets are metrizable the following…

Functional Analysis · Mathematics 2018-09-25 Saak Gabriyelyan

Let $T$ be a topological space admitting a compatible proper metric, that is, a locally compact, separable and metrisable space. Let $\mathcal{M}^T$ be the non-empty set of all proper metrics $d$ on $T$ compatible with its topology, and…

Functional Analysis · Mathematics 2023-11-17 Richard J. Smith , Filip Talimdjioski

We study the structure of Busemann spaces with measures satisfying the measure contraction property (MCP). The main results are rigidity theorems and structure theorems under the assumption of geodesic completeness or non-collapse. The…

Differential Geometry · Mathematics 2026-04-20 Tadashi Fujioka , Kenshiro Tashiro

In the past few decades, much has been done regarding the descriptive set theory of separable Banach spaces. However, the descriptive properties of separable Fr\'echet spaces have not yet been investigated. In these notes, we look at this…

Functional Analysis · Mathematics 2025-08-14 Bruno de Mendonça Braga , Willian Hans Goes Corrêa , Valentin Ferenczi

Hurewicz' characterized the dimension of separable metrizable spaces by means of finite-to-one maps. We investigate whether this characterization also holds in the class of compact F-spaces of weight c. Our main result is that, assuming the…

General Topology · Mathematics 2014-01-15 Klaas Pieter Hart , Jan van Mill

Newtonian spaces generalize first-order Sobolev spaces to abstract metric measure spaces. In this paper, we study regularity of Newtonian functions based on quasi-Banach function lattices. Their (weak) quasi-continuity is established,…

Functional Analysis · Mathematics 2016-09-23 Lukáš Malý

We characterize measure spaces such that the canonical map $L_\infty \to L_1^*$ is surjective. In case of $d$ dimensional Hausdorff measure of a complete separable metric space $X$ we give two equivalent conditions. One is in terms of the…

Functional Analysis · Mathematics 2020-06-05 Thierry De Pauw

We analyze the properties of weakly compact sets in Lipschitz free spaces. Prior research has established that, for a complete metric space $M$, weakly precompact sets in the Lipschitz free space $\mathcal F(M)$ are tight. In this paper, we…

Functional Analysis · Mathematics 2026-02-16 Ramón J. Aliaga , Colin Petitjean , Antonín Prochazka , Triinu Veeorg

A convergence structure generalizing the order convergence structure on the set of Hausdorff continuous interval functions is defined on the set of minimal usco maps. The properties of the obtained convergence space are investigated and…

General Topology · Mathematics 2007-05-23 R Anguelov , O. F. K. Kalenda

We characterise purely $n$-unrectifiable subsets $S$ of a complete metric space $X$ with finite Hausdorff $n$-measure by studying arbitrarily small perturbations of elements of the set of all bounded 1-Lipschitz functions $f\colon X \to…

Metric Geometry · Mathematics 2020-04-02 David Bate

In this paper, we study the nonexpansive properties of metric resolvent, and present a convergence rate analysis for the associated fixed-point iterations (Banach-Picard and Krasnosel'skii-Mann types). Equipped with a variable metric, we…

Optimization and Control · Mathematics 2021-09-14 Feng Xue

A metric space (X,d) is monotone if there is a linear order < on X and a constant c>0 such that d(x,y) < c d(x,z) for all x<y<z in X. Properties of continuous functions with monotone graph (considered as a planar set) are investigated. It…

Classical Analysis and ODEs · Mathematics 2012-10-09 Ondřej Zindulka , Michael Hrušák , Tamás Mátrai , Aleš Nekvinda , Václav Vlasák

In this long note, we investigate various purely topological aspects of non-Hausdorff manifolds (NH-manifolds for short). Our emphasis is on manifolds which exhibit homogeneity or weakenings thereof, in particular being everywhere…

General Topology · Mathematics 2026-03-26 Mathieu Baillif

We construct \emph{intrinsic} metrics on the Strichartz hexacarpet using weight functions and show that these metrics do \emph{not} satisfy the chain condition. We give uniform Harnack inequality on the approximating graphs of the…

Functional Analysis · Mathematics 2019-11-11 Meng Yang