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Related papers: Genericity and Universality for Operator Ideals

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We propose a unifying approach to many approximation properties studied in the literature from the 1930s up to our days. To do so, we say that a Banach space E has the (I,J,{\tau})-approximation property if E-valued operators belonging to…

Functional Analysis · Mathematics 2013-07-31 Sonia Berrios , Geraldo Botelho

We show that if an infinite-dimensional Banach space X has a symmetric basis then there exists a bounded, linear operator R : X --> X such that the set A = {x in X : ||R^n(x)|| --> infinity} is non-empty and nowhere dense in X. Moreover, if…

Functional Analysis · Mathematics 2022-06-14 Petr Hajek , Richard J. Smith

This paper investigates advanced notions of lineability and spaceability within the frameworks of sequence spaces and operator ideals. We propose the notion of \emph{Standard Sequence Classes} to provide an environment that unifies numerous…

Functional Analysis · Mathematics 2026-02-12 Nacib G. Albuquerque , Jamilson R. Campos , Luiz Felipe P. Sousa

We study the ideals of linear operators between Banach spaces determined by the transformation of vector-valued sequences involving the new sequence space introduced by Karn and Sinha \cite{karnsinha} and the classical spaces of absolutely,…

Functional Analysis · Mathematics 2017-03-01 Geraldo Botelho , Jamilson R. Campos , Joedson Santos

We prove when a Banach ideal of linear operators defined, or characterized, by the transformation of vector-valued sequences is maximal. Known results are recovered as particular cases and new information is obtained. To accomplish this…

Functional Analysis · Mathematics 2022-06-22 Geraldo Botelho , Jamilson R. Campos , Lucas Nascimento

We show that for each Banach ideal of homogeneous polynomials, there exists a (necessarily unique) Banach operator ideal compatible with it. Analogously, we prove that any ideal of $n$-homogeneous polynomials belongs to a coherent sequence…

Functional Analysis · Mathematics 2012-01-20 Daniel Carando , Verónica Dimant , Santiago Muro

Let $\lambda$ be an infinite cardinal number and let $\ell_\infty^c(\lambda)$ denote the subspace of $\ell_\infty(\lambda)$ consisting of all functions that assume at most countably many non-zero values. We classify all infinite dimensional…

Functional Analysis · Mathematics 2016-10-26 William B. Johnson , Tomasz Kania , Gideon Schechtman

We present some properties of orthogonality and relate them with support disjoint and norm inequalities in p Schatten ideals. In addition, we investigate the problem of characterization of norm parallelism for bounded linear operators. We…

Functional Analysis · Mathematics 2021-07-23 T. Bottazzi , C. Conde , M. S. Moslehian , P. Wojcik , A. Zamani

It is well known that weakly $p$-summable sequences in a Banach space $E$ are associated to bounded operators from $\ell_{p^*}$ to $E$, and unconditionally $p$-summable sequences in $E$ are associated to compact operators from $\ell_{p^*}$…

Functional Analysis · Mathematics 2024-03-07 Geraldo Botelho , Ariel S. Santiago

Given two quasi-Banach ideals \oid{A}{}{} and \oid{B}{}{} we investigate the regular hull of their composition - $(\oid{A}{}{} \circ \oid{B}{}{})^{reg}$. In concrete situations this regular hull appears more often than the composition…

Functional Analysis · Mathematics 2016-09-06 Frank Oertel

We formulate general conditions which imply that $L(X,Y)$, the space of operators from a Banach space $X$ to a Banach space $Y$, has $2^{\mathfrak c}$ closed ideals where $\mathfrak c$ is the cardinality of the continuum. These results are…

Functional Analysis · Mathematics 2020-08-25 Daniel Freeman , Thomas Schlumprecht , Andras Zsak

Let $\mathcal{I,J}$ be symmetric quasi-Banach ideals of compact operators on an infinite-dimensional complex Hilbert space $H$, let $\mathcal{J:I}$ be a space of multipliers from $\mathcal{I}$ to $\mathcal{J}$. Obviously, ideals…

Operator Algebras · Mathematics 2012-04-23 A. F. Ber , V. I. Chilin , G. B. Levitina , F. A. Sukochev

Let $\mathscr{B}(X)$ denote the Banach algebra of bounded operators on $X$, where~$X$ is either Tsirelson's Banach space or the Schreier space of order $n$ for some $n\in\mathbb N$. We show that the lattice of closed ideals…

Functional Analysis · Mathematics 2020-04-14 Kevin Beanland , Tomasz Kania , Niels Jakob Laustsen

The purpose of the present work is to treat a new notion related to linear dynamics, which can be viewed as a "localization" of the notion of hypercyclicity. In particular, let $T$ be a bounded linear operator acting on a Banach space $X$…

Functional Analysis · Mathematics 2009-03-12 George Costakis , Antonios Manoussos

We consider linear operators defined on a subspace of a complex Banach space into its topological antidual acting positively in a natural sense. The goal of this paper is to investigate of this kind of operators. The main theorem is a…

Functional Analysis · Mathematics 2014-09-12 Zoltán Sebestyén , Zsolt Szűcs , Zsigmond Tarcsay

This article - a part of a multipaper project investigating arithmetic mean ideals - investigates the codimension of commutator spaces [I, B(H)] of operator ideals on a separable Hilbert space, i.e., ``How many traces can an ideal support?"…

Functional Analysis · Mathematics 2007-07-24 Victor Kaftal , Gary Weiss

We introduce the class of operator $p$-compact mappings and completely right $p$-nuclear operators, which are natural extensions to the operator space framework of their corresponding Banach operator ideals. We relate these two classes,…

Functional Analysis · Mathematics 2018-09-21 Javier Alejandro Chávez-Domínguez , Verónica Dimant , Daniel Galicer

The theory of M-ideals and multiplier mappings of Banach spaces naturally generalizes to left (or right) M-ideals and multiplier mappings of operator spaces. These subspaces and mappings are intrinsically characterized in terms of the…

Operator Algebras · Mathematics 2007-05-23 David P. Blecher , Edward G. Effros , Vrej Zarikian

Let $T$ be a bounded linear operator on a (real or complex) Banach space $X$. If $(a_n)$ is a sequence of non-negative numbers tending to 0. Then, the set of $x \in X$ such that $\|T^nx\| \geqslant a_n \|T^n\|$ for infinitely many $n$'s has…

Functional Analysis · Mathematics 2012-04-11 Jean-Matthieu Augé

Let $X,Y$ be Banach spaces, and fix a linear operator $T \in \mathcal{L}(X,Y)$, and ideals $\mathcal{I}, \mathcal{J}$ on $\omega$. We obtain Silverman--Toeplitz type theorems on matrices $A=(A_{n,k}: n,k \in \omega)$ of linear operators in…

Functional Analysis · Mathematics 2025-08-20 Paolo Leonetti