English
Related papers

Related papers: Weak-star quasi norm attaining operators

200 papers

In this paper, we will study some properties of b-weakly compact operators and we will investigate their relationships to some variety of operators on the normed vector lattices. With some new conditions, we show that the modulus of an…

Functional Analysis · Mathematics 2019-05-28 Kazem Haghnejad Azar

In this paper we give a various conditions for which the tuple $\mathcal{T} = (T_{1} , T_{2} , ... , T_{n})$ of commutative bounded linear operators on an infinite dimensional ( real , complex ) Banach space X is orbit reflexive. After we…

Functional Analysis · Mathematics 2018-12-19 Abdelaziz Tajmouati , Youness Zahouan

We study approximately orthogonality (in the sense of Dragomir) preserving and reversing operators. We show that for some orthogonality notations, an operator defined from a finite-dimensional Banach space to a normed linear space is…

Functional Analysis · Mathematics 2025-12-11 Divya Khurana

We study uniform $\epsilon-$BPB approximations of bounded linear operators between Banach spaces from a geometric perspective. We show that for sufficiently small positive values of $\epsilon,$ many geometric properties like smoothness,…

Functional Analysis · Mathematics 2024-08-14 Debmalya Sain , Arpita Mal , Kalidas Mandal , Kallol Paul

In this paper, almost Dunford-Pettis operators with ranges in $c_0$ are used to identify totally bounded sets in the absolute weak topology. That is, a bounded subset $A$ of a Banach lattice $E$ is $|\sigma|(E,E^\prime)$-totally bounded if…

Functional Analysis · Mathematics 2024-06-14 Halimeh Ardakani , Jin Xi Chen

We prove that in a metric measure space $X$, if for some $p \in (1,\infty)$ there are uniform bounds (independent of the measure) for the weak type $(p,p)$ of the centered maximal operator, then $X$ satisfies a certain geometric condition,…

Classical Analysis and ODEs · Mathematics 2020-03-11 J. M. Aldaz

We introduce the class of unbounded $M$-weakly operators and the class of unbounded $L$-weakly compact operators. We investigate some properties for these new classification of operators and we study relation between them and $M$-weakly…

Functional Analysis · Mathematics 2021-09-16 Zahra Niktab , Kazem Haghnejad Azar , Razi Alavizadeh , Saba Sadeghi Gavgani

The concept of uniform convexity of a Banach space was generalized to linear operators between Banach spaces and studied by Beauzamy [1976]. Under this generalization, a Banach space X is uniformly convex if and only if its identity map I_X…

Functional Analysis · Mathematics 2007-05-23 J Wenzel

In this work, we study non-rough norms in L(X,Y), the space of bounded linear operators between Banach spaces X and Y. We prove that L(X,Y) has non-rough norm if and only if X* and Y have non-rough norm. We show that the injective tensor…

Functional Analysis · Mathematics 2022-10-19 Susmita Seal , Sudeshna Basu , Julio Becerra Guerrero , Juan Miguel Villegas Yeguas

A nonempty closed convex bounded subset $C$ of a Banach space is said to have the weak approximate fixed point property if for every continuous map $f:C\to C$ there is a sequence $\{x_n\}$ in $C$ such that $x_n-f(x_n)$ converge weakly to 0.…

Functional Analysis · Mathematics 2011-03-18 Ondřej F. K. Kalenda

We analyze various consequences in relation to the extension of operators $T:X\to Y$ that are $p$-compact, as well as the extension of operators $T:X\to Y$ whose adjoints $T^*:Y^*\to X^*$ are $p$-compact. In most cases, we discuss these…

Functional Analysis · Mathematics 2026-01-27 Sainik Karak , Tanmoy Paul

Let $(X, d, \mu)$ be a space of homogeneous type and $\Omega$ an open subset of $X$. Given a bounded operator $T: L^p(\Omega) \to L^q(\Omega)$ for some $1 \le p \le q < \infty$, we give a criterion for $T$ to be of weak type $(p_0, a)$ for…

Functional Analysis · Mathematics 2026-05-14 Bernhard H. Haak , El-Maati Ouhabaz

Suppose $X$ and $Y$ are Banach spaces, $K$ is a compact Hausdorff space, $\Sigma$ is the $\sigma$-algebra of Borel subsets of $K$, $C(K,X)$ is the Banach space of all continuous $X$-valued functions (with the supremum norm), and…

Functional Analysis · Mathematics 2023-12-13 Ioana Ghenciu , Roxana Popescu

We characterize the weak-star point of continuity property for subspaces of dual spaces with separable predual and we deduce that the weak-star point of continuity property is determined by subspaces with a Schauder basis in the natural…

Functional Analysis · Mathematics 2013-09-17 Ginés López Pérez , José A. Soler Arias

A bounded subset $M$ of a Banach space $X$ is said to be $\varepsilon$-weakly precompact, for a given $\varepsilon\geq 0$, if every sequence $(x_n)_{n\in \mathbb{N}}$ in $M$ admits a subsequence $(x_{n_k})_{k\in \mathbb{N}}$ such that $$…

Functional Analysis · Mathematics 2021-02-03 José Rodríguez

Resolvents of quasi-linear operators and operator algebras in Banach spaces over the quaternion field are investigated. Spectral theory of unbounded nonlinear operators in quaternion Banach spaces is studied. Strongly continuous semigroups…

Operator Algebras · Mathematics 2018-12-18 S. V. Ludkovsky

This paper provides conditions (i) to distinguish weak supercyclicity form supercyclicity for operators acting on normed and Banach spaces, and also (ii) to ensure when weak supercyclicity implies weak stability.

Functional Analysis · Mathematics 2021-01-26 C. S. Kubrusly , B. P. Duggal

The purpose of this article is to study the anti-coproximinal and strongly anti-coproximinal subspaces of the Banach space of all bounded (continuous) functions. We obtain a tractable necessary condition for a subspace to be stronsgly…

Functional Analysis · Mathematics 2026-02-02 Shamim Sohel , Souvik Ghosh , Debmalya Sain , Kallol Paul

This paper investigates the boundedness of a broad class of operators within the framework of generalized Morrey-Banach function spaces. This class includes multilinear operators such as multilinear $\omega$-Calder\'{o}n-Zygmund operators,…

Classical Analysis and ODEs · Mathematics 2025-02-13 Jiawei Tan , Jiahui Wang , Qingying Xue

Given a Banach space $E$, we ask which closed subspaces may be realised as the kernel of a bounded operator $E \rightarrow E$. We prove some positive results which imply in particular that when $E$ is separable every closed subspace is a…

Functional Analysis · Mathematics 2018-11-30 Niels Jakob Laustsen , Jared T. White
‹ Prev 1 8 9 10 Next ›