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Related papers: A property in vector-valued function spaces

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We will introduce the countable separation property (CSP) of Banach spaces X, which is defined as follows: For each subset \mathcal{F} of X^{\ast}, which separates X, there exists a countable separating subset \mathcal{F}_{0} of…

Functional Analysis · Mathematics 2008-04-10 Jarno Talponen

We consider the fractional derivative of a general Poisson semigroup. With this fractional derivative we define the generalized fractional Littlewood-Paley $g$-function for semigroups acting on $L^p$-spaces of functions with values in…

Functional Analysis · Mathematics 2011-08-31 José L. Torrea , Chao Zhang

Several new characterizations of the Gelfand-Phillips property are given. We define a strong version of the Gelfand-Phillips property and prove that a Banach space has this stronger property iff it embeds into $c_0$. For an infinite compact…

Functional Analysis · Mathematics 2021-10-18 Taras Banakh , Saak Gabriyelyan

We characterise those Banach spaces $X$ which satisfy that $L(Y,X)$ is octahedral for every non-zero Banach space $Y$. They are those satisfying that, for every finite dimensional subspace $Z$, $\ell_\infty$ can be finitely-representable in…

Functional Analysis · Mathematics 2022-12-13 Abraham Rueda Zoca

The classical Mazur map is a uniform homeomorphism between the unit spheres of $L_p$ spaces, and the version for noncommutative $L_p$ spaces has the same property. Odell and Schlumprecht used two types of generalized Mazur maps to prove…

Functional Analysis · Mathematics 2023-05-15 Javier Alejandro Chávez-Domínguez

We study a relation between three different formulations of theorems on separable determination - one using the concept of rich families, second via the concept of suitable models and third, a new one, suggested in this paper, using the…

Functional Analysis · Mathematics 2019-01-30 Marek Cuth

In this note, we observe that $X\in (GC)$ if $X$ admits Chebyshev center for any finite set in it. This answers the problem raised by Vesel\'y, addressed in [{\em Generalized centers of finite sets in Banach spaces}, Acta Math. Univ.…

Functional Analysis · Mathematics 2026-01-09 Syamantak Das , Tanmoy Paul

A subspace $X$ of a Banach space $Y$ has $\textit{Property U}$ whenever every continuous linear functional on $X$ has a unique norm-preserving (i.e., Hahn$-$Banach) extension to $Y$ (Phelps, 1960). Throughout this document we introduce and…

Functional Analysis · Mathematics 2022-11-22 Ch. Cobollo , A. J. Guirao , V. Montesinos

If $X$ is an infinite-dimensional uniform algebra, if $X$ has the Daugavet property or if $X$ is a proper $M$-embedded space, every relatively weakly open subset of the unit ball of the Banach space $X$ is known to have diameter 2, i.e.,…

Functional Analysis · Mathematics 2013-04-29 Trond Abrahamsen , Vegard Lima , Olav Nygaard

In this paper we give a simple proof of inequalities of integrals of functions which are the composition of nonnegative continous convex functions on a vector space ${\bf R}^m$ and vector-valued functions in a weakly compact subset of a…

Functional Analysis · Mathematics 2007-08-27 Zhenglu Jiang , Xiaoyong Fu , Hongjiong Tian

Let $A$ be a commutative semisimple Banach algebra, $X$ be a locally compact Hausdorff topological space and $G$ be a locally compact topological group. In this paper, we investigate several properties of vector valued Banach algebras…

Functional Analysis · Mathematics 2022-01-04 Ali Rejali , Mitra Amiri

We prove that several classical Banach space properties are equivalent to separability for the class of Lipschitz-free spaces, including Corson's property ($\mathcal{C}$), Talponen's Countable Separation Property, or being a G\^ateaux…

Functional Analysis · Mathematics 2024-04-08 Ramón J. Aliaga , Guillaume Grelier , Antonín Procházka

We define and study the notion of property $(\rm T)$ for Banach algebras, generalizing the one from $C^*$-algebras. For a second countable locally compact group $G$ and a given family of Banach spaces $\mathcal E$, we prove that our Banach…

Functional Analysis · Mathematics 2024-08-23 Emilie Mai Elkiær , Sanaz Pooya

The geometric notion of huskability initiated and developed in [B3], [BR] ,[EW], [GM] was subsequently extensively studied in the context of dentability and Radon Nikodym Property in [GGMS]. In this work, we introduce a new geometric…

Functional Analysis · Mathematics 2021-08-06 Sudeshna Basu , Susmita Seal

It is shown that a Banach space with locally uniformly convex dual admits an equivalent norm which is itself locally uniformly convex. It follows that on any such space all continuous real-valued functions may be uniformly approximated by…

Functional Analysis · Mathematics 2007-05-23 Richard Haydon

The classical Mazur-Ulam theorem establishes that every surjective isometry between normed real vector spaces is an affine transformation. In various applied mathematical settings, however, one encounters maps that preserve distances not…

Probability · Mathematics 2026-01-08 Justinas Zaliaduonis , Sergios Gatidis

J. L. Rubio de Francia proved the one-sided Littlewood--Paley inequality for arbitrary intervals in $L^p$, $2\le p<\infty$ and later N. N. Osipov proved the similar inequality for Walsh functions. In this paper we investigate some…

Functional Analysis · Mathematics 2021-11-16 Anton Tselishchev

We prove that every JBW$^*$-triple $M$ with rank one or rank bigger than or equal to three satisfies the Mazur--Ulam property, that is, every surjective isometry from the unit sphere of $M$ onto the unit sphere of another Banach space $Y$…

We set up a descriptive set-theoretic framework to study Lipschitz-free spaces and use the reduction argument of Bossard to prove several results. We prove two universality results: if a separable Banach space is isomorphically universal…

Functional Analysis · Mathematics 2026-02-24 Richard J. Smith

In this paper we deal with two weaker forms of injectivity which turn out to have a rich structure behind: separable injectivity and universal separable injectivity. We show several structural and stability properties of these classes of…

Functional Analysis · Mathematics 2017-03-29 Antonio Aviles , Felix Cabello , Jesus M. F. Castillo , Manuel Gonzalez , Yolanda Moreno