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Related papers: I-Completeness in Function Spaces

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The aim of the note is to extend the uniformization theorem to compact Kahler spaces X with mild singularities and establish a kind of rigidity of their universal coverings. We assume the fundamental group of X is large, residually finite…

Algebraic Geometry · Mathematics 2016-08-01 Robert Treger

Some new classes of compacta $K$ are considered for which $C(K)$ endowed with the pointwise topology has a countable cover by sets of small local norm--diameter.

Functional Analysis · Mathematics 2015-10-20 Wiesław Kubiś , Aníbal Moltó , Stanimir Troyanski

We introduce the notion of uniform exactness, or uniform amenability at infinity, for discrete groups and prove it for a wide class of groups containing free groups and their limit groups. This shows a novel strong convergence phenomenon…

Group Theory · Mathematics 2026-05-01 Narutaka Ozawa

We introduce and study two new relations between function spaces over measure spaces of infinite measure, motivated by the question of establishing compactness. The first relation captures the uniform decay of function (quasi-)norms ``at…

Functional Analysis · Mathematics 2025-11-25 Zdeněk Mihula , Maximilián Pándy

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

A function $f:X\to Y$ between topological spaces is called {\em compact-preserving} if the image $f(K)$ of each compact subset $K\subset X$ is compact. We prove that a function $f:X\to Y$ defined on a strong Frechet space $X$ is…

General Topology · Mathematics 2013-05-28 Taras Banakh , Artur Bartoszewicz , Marek Bienias , Szymon Glab

For a completely regular space $X$, denote by $C_p(X)$ the space of continuous real-valued functions on $X$, with the pointwise convergence topology. In this article we strengthen a theorem of O. Okunev concerning preservation of some…

General Topology · Mathematics 2023-09-28 Mikolaj Krupski

Metric spaces satisfying properties stronger than completeness and weaker than compactness have been studied by many authors over the years. One such significant family is that of cofinally complete metric spaces. We discuss the…

General Topology · Mathematics 2018-07-12 Lipsy , Manisha Aggarwal , S. Kundu

Some concepts, such as non-compactness measure and condensing operators, defined on metric spaces are extended to uniform spaces. Such extensions allow us to locate, in the context of uniform spaces, some classical results existing in…

General Topology · Mathematics 2015-11-25 Raúl Fierro

We investigate under which condition the $\kappa$-ind completion of a functor category $C^I$ is equivalent to the category of functors from $I$ to the $\kappa$-ind completion of $C$. A published theorem implies this is true for any Cauchy…

Category Theory · Mathematics 2024-10-10 Simon Henry

For separable metrizable spaces $X,Y$ and a metrizable topological group $Z$ by $S(X\times Y,Z)$ we denote the space of all separately continuous functions $f:X\times Y\to Z$ endowed with the topology of layer-wise uniform convergence,…

General Topology · Mathematics 2016-02-23 Taras Banakh

A compact space X is I-favorable if, and only if X can be representing as a limit of $\sigma$-complete inverse system of compact metrizable spaces with skeletal bonding maps.

General Topology · Mathematics 2008-03-03 Andrzej Kucharski , Szymon Plewik

We discuss some notions of compactness and convergence relative to a specified family F of subsets of some topological space X. The two most interesting particular cases of our construction appear to be the following ones. (1) The case in…

General Topology · Mathematics 2011-06-07 Paolo Lipparini

We study universal approximation of continuous functionals on compact subsets of products of Hilbert spaces. We prove that any such functional can be uniformly approximated by models that first take finitely many continuous linear…

Machine Learning · Computer Science 2026-02-04 Andrey Krylov , Maksim Penkin

We extend Beem's three completeness notions -- finite compactness, timelike Cauchy completeness, and Condition A -- originally defined for spacetimes, to Lorentzian length spaces and study their relationships. We prove that finite…

Differential Geometry · Mathematics 2026-02-04 Keita Takahashi

The concept of convex compactness, weaker than the classical notion of compactness, is introduced and discussed. It is shown that a large class of convex subsets of topological vector spaces shares this property and that is can be used in…

Functional Analysis · Mathematics 2010-06-02 Gordan Zitkovic

In this paper, we study the existence of fixed points for mappings defined on complete, (sequentially compact) cone metric spaces, satisfying a general contractive inequality depending of two additional mappings.

Functional Analysis · Mathematics 2015-02-17 José R. Morales , Edixon Rojas

This work introduces the concept of an M-complete approximate identity (M-cai) for a given operator subspace X of an operator space Y. M-cai's generalize central approximate identities in ideals in $C^*$-algebras, for it is proved that if X…

Operator Algebras · Mathematics 2007-05-23 A. Arias , Haskell P. Rosenthal

In this paper, we prove necessary and sufficient conditions for a sense-preserving harmonic function to be absolutely convex in the open unit disk. We also estimate the coefficient bound and obtain growth, covering and area theorems for…

Complex Variables · Mathematics 2016-05-10 Saminathan Ponnusamy , Anbareeswaran Sairam Kaliraj , Victor V. Starkov

We study the classification of spaces of continuous functions $C(K)$ under positive linear maps. For infinite countable compacta, we show that whenever $C(K)$ and $C(L)$ are isomorphic, there exists an isomorphism $T:C(K)\to C(L)$…

Functional Analysis · Mathematics 2026-01-19 Marek Cúth , Jonáš Havelka , Jakub Rondoš , Bünyamin Sarı