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Related papers: Function spaces not containing $\ell_{1}$

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We construct a Banach space $X$ for which the set of norm-attaining functionals $NA(X,\mathbb{R})$ does not contain any non-trivial cone. Even more, given two linearly independent norm-attaining functionals on $X$, no other element of the…

Functional Analysis · Mathematics 2025-01-08 Miguel Martin

Assume that $\Omega\subset \mathbb{R}^k$ is an open set, $V$ is a separable Banach space over a field $\mathbb K\in\{\mathbb R,\mathbb C\}$ and $f_1,\ldots,f_N \colon\Omega\to \Omega$, $g_1,\ldots, g_N\colon\Omega\to \mathbb{K}$, $h_0\colon…

Classical Analysis and ODEs · Mathematics 2021-01-08 Janusz Morawiec , Thomas Zürcher

We study homomorphisms on the algebra of analytic functions of bounded type on a Banach space. When the domain space lacks symmetric regularity, we show that in every fiber of the spectrum there are evaluations (in higher duals) which do…

Functional Analysis · Mathematics 2022-06-15 Daniel Carando , Verónica Dimant , Jorge Tomás Rodríguez

We study the problem of existence and uniqueness of isometric Banach preduals of a Banach space. We derive necessary and sufficient conditions for the existence of an isometric Banach predual of a Banach space $X$. Then we focus on the case…

Functional Analysis · Mathematics 2023-08-01 Karsten Kruse

Let $X$ be a Banach space. We prove that, for a large class of Banach or quasi-Banach spaces $E$ of $X$-valued sequences, the sets $E-\bigcup _{q\in\Gamma}\ell_{q}(X)$, where $\Gamma$ is any subset of $(0,\infty]$, and $E-c_{0}(X)$ contain…

Functional Analysis · Mathematics 2012-08-30 G. Botelho , D. Diniz , V. V. Favaro , D. Pellegrino

We investigate some properties of (universal) Banach spaces of real functions in the context of topological entropy. Among other things, we show that any subspace of $C([0,1])$ which is isometrically isomorphic to $\ell_1$ contains a…

Dynamical Systems · Mathematics 2011-06-02 Jozef Bobok , Henk Bruin

James Tree Space ($\mathcal{JT}$), introduced by R. James, is the first Banach space constructed having non-separable conjugate and not containing $\ell^1$. James actually proved that every infinite dimensional subspace of $\mathcal{JT}$…

Functional Analysis · Mathematics 2021-08-23 Ioakeim Ampatzoglou

We present some extensions of classical results that involve elements of the dual of Banach spaces, such as Bishop-Phelp's theorem and James' compactness theorem, but restricting to sets of functionals determined by geometrical properties.…

Functional Analysis · Mathematics 2015-08-04 Bernardo Cascales , José Orihuela , Antonio Pérez

In this paper, we construct maximally monotone operators that are not of Gossez's dense-type (D) in many nonreflexive spaces. Many of these operators also fail to possess the Br{\o}nsted-Rockafellar (BR) property. Using these operators, we…

Functional Analysis · Mathematics 2011-08-09 Heinz H. Bauschke , Jonathan M. Borwein , Xianfu Wang , Liangjin Yao

A function space, $L^{\theta,\infty)}(\Omega)$, $0 \leq \theta <\infty$, is defined. It is proved that $L^{\theta,\infty)}(\Omega)$ is a Banach space which is a generalization of exponential class. An alternative definition of…

Analysis of PDEs · Mathematics 2018-12-20 Hongya Gao , Chao Liu , Hong Tian

This paper is concerned with the algebraic dual D*(\Omega) of the space of test functions D(\Omega). The emphasis is on failures and successes of D*(\Omega) as compared to the continuous dual D'(\Omega), the space of distributions.…

Functional Analysis · Mathematics 2019-03-18 Michael Oberguggenberger

An open chain cover $\{U_\alpha : \alpha\in\kappa\}$ ($\kappa$ a cardinal) of a space $X$ is a systematic cover if the closure of $U_\alpha$ is contained in $U_\beta$ when $\alpha<\beta$, and $X$ is Type I if $\kappa=\omega_1$ and the…

General Topology · Mathematics 2022-08-23 Mathieu Baillif

On a reflexive Banach space $X$, if an operator $T$ admits a functional calculus for the absolutely continuous functions on its spectrum $\sigma(T) \subseteq \mathbb{R}$, then this functional calculus can always be extended to include all…

Functional Analysis · Mathematics 2011-06-27 Ian Doust , Venta Terauds

Motivated by recent work on strict deformation quantization of the unit disk and the Riemann sphere, we study the Fr\'echet space structure of the set of holomorphic functions on the complement $\Omega:=\{(z,w)\in \hat{\mathbb{C}}^2\, :\,…

Complex Variables · Mathematics 2024-04-16 Michael Heins , Annika Moucha , Oliver Roth

Let $X$ be a Banach space with a separable dual. We prove that $X$ embeds isomorphically into a $\cL_\infty$ space $Z$ whose dual is isomorphic to $\ell_1$. If, moreover, $U$ is a space so that $U$ and $X$ are totally incomparable, then we…

Functional Analysis · Mathematics 2010-05-17 Daniel Freeman , Edward Odell , Thomas Schlumprecht

We present an example of an infinite dimensional separable space of affine continuous functions on a Choquet simplex that does not contain a subspace linearly isometric to $c$. This example disproves a result stated in M. Zippin. On some…

Functional Analysis · Mathematics 2015-04-01 Emanuele Casini , Enrico Miglierina , Łukasz Piasecki

Let ${T_1,...,T_l}$ be a collection of differential operators with constant coefficients on the torus $\mathbb{T}^n$. Consider the Banach space $X$ of functions $f$ on the torus for which all functions $T_j f$, $j=1,...,l$, are continuous.…

Functional Analysis · Mathematics 2016-03-29 S. V. Kislyakov , D. V. Maksimov , D. M. Stolyarov

Given a Banach space $E$ consisting of functions, we ask whether there exists a reproducing kernel Hilbert space $H$ with bounded kernel such that $E\subset H$. More generally, we consider the question, whether for a given Banach space…

Functional Analysis · Mathematics 2024-02-21 Max Schölpple , Ingo Steinwart

For a metrizable space $X$ and a finite measure space $(\Omega,\mathfrak{M},\mu)$ let $M_{\mu}(X)$ and $M^f_{\mu}(X)$ be the spaces of all equivalence classes (under the relation of equality almost everywhere mod $\mu$) of…

General Topology · Mathematics 2013-05-07 Piotr Niemiec

It is hereby established that the set of Lipschitz functions $f:\mathcal{U}\rightarrow \mathbb{R}$ ($\mathcal{U}$ nonempty open subset of $\ell_{d}^{1}$) with maximal Clarke subdifferential contains a linear subspace of uncountable…

Functional Analysis · Mathematics 2023-05-22 Aris Daniilidis , Gonzalo Flores