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Related papers: New norm estimate for composition operators

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We study a composition operator on Lorentz spaces. In particular we provide necessary and sufficient conditions under which a measurable mapping induces a bounded composition operator.

Functional Analysis · Mathematics 2021-05-27 Nikita Evseev

We introduce a new norm on the space of bounded linear operators on a complex Hilbert space, which generalizes the numerical radius norm, the usual operator norm and the modified Davis-Wielandt radius. We study basic properties of this…

Functional Analysis · Mathematics 2024-08-14 D. Sain , P. Bhunia , A. Bhanja , K. Paul

In this study, we investigate the boundedness of composition operators acting on Morrey spaces and weak Morrey spaces. The primary aim of this study is to investigate a necessary and sufficient condition on the boundedness of the…

Functional Analysis · Mathematics 2020-08-31 Naoya Hatano , Masahiro Ikeda , Isao Ishikawa , Yoshihiro Sawano

The boundedness and compactness of weighted composition operators from $H^\infty$ to the Bloch space in the unit ball of Cn are investigated in this paper. In particular, some new characterizations for the boundedness and the essential norm…

Complex Variables · Mathematics 2018-01-08 Juntao Du , Songxiao Li

We prove that the norm of a weighted composition operator on the Hardy space H^2 of the disk is controlled by the norm of the weight function in the de Branges-Rovnyak space associated to the symbol of the composition operator. As a…

Functional Analysis · Mathematics 2007-07-24 Michael T. Jury

In this paper, we investigate weighted composition, Volterra and Integral operators on second derivative Hardy spaces. Some equivalent conditions for boundedness of the operators will be given using the boundedness on the Hardy spaces. Also…

Functional Analysis · Mathematics 2022-10-13 Mostafa Hassanlou , Ebrahim Abbasi

We consider the products of composition and differentiation operators on the Hardy space. We provide a complete characterization of the boundedness and compactness of these operators. Furthermore, we obtain the explicit condition for these…

Functional Analysis · Mathematics 2021-08-17 Mahbube Moradi , Mahsa Fatehi

The main purpose of this paper is to investigate characterizations of composition operators on Bloch and Hardy type spaces. Initially, we use general doubling weights to study the composition operators from harmonic Bloch type spaces on the…

Complex Variables · Mathematics 2023-12-11 Shaolin Chen , Hidetaka Hamada

A unified approach to the concept of a Hausdorff operator is proposed in such a way that a number of classical and new operators feet into the given definition. Conditions are given for the boundedness of the operators under consideration…

Functional Analysis · Mathematics 2024-06-18 A. R. Mirotin

We complete the different cases remaining in the estimation of the essential norm of a weighted composition operator acting between the Hardy spaces $H^p$ and $H^q$ for $1\leq p,q\leq\infty.$ In particular we give some estimates for the…

Functional Analysis · Mathematics 2011-10-25 Romain Demazeux

In this paper, we study some operators which are originated from classical Littlewood-Paley theory. We consider their modification with respect to our discontinuous setup, where the underlying process is the product of a one dimensional…

Probability · Mathematics 2016-06-16 Deniz Karli

By a theorem of Bayart, $\varphi$ generates a bounded composition operator on the Hardy space $\Hp$of Dirichlet series ($1\le p<\infty$) only if $\varphi(s)=c_0 s+\psi(s)$, where $c_0$ is a nonnegative integer and $\psi$ a Dirichlet series…

Functional Analysis · Mathematics 2016-02-26 Frédéric Bayart , Hervé Queffélec , Kristian Seip

We obtain non-Euclidean versions of classical theorems due to Hardy and Littlewood concerning smoothness of the boundary function of an analytic mapping on the unit disk with an appropriate growth condition.

Complex Variables · Mathematics 2024-05-28 Marijan Markovic

We give a necessary and sufficient condition for a holomorphic self-map $\phi$ of the tridisc to induce a bounded composition operator on the associated Hardy space. This condition depends on the behaviour of the first and the second…

Functional Analysis · Mathematics 2023-12-06 Frédéric Bayart

A criterion for subnormality of unbounded composition operators in L2-spaces, written in terms of measurable families of probability measures satisfying the so-called consistency condition, is established. It becomes a new characterization…

Functional Analysis · Mathematics 2013-03-27 Piotr Budzynski , Zenon Jan Jablonski , Il Bong Jung , Jan Stochel

This paper aims to study the boundedness and compactness of composition operators from model spaces to the Hardy Hilbert spaces in the upper half-plane. Consequently, we investigate the boundedness and compactness of composition operators…

Functional Analysis · Mathematics 2026-05-13 Bharti Garg , Subhankar Mahapatra , Santanu Sarkar

We establish necessary and sufficient conditions for the boundedness and compactness of weighted composition operators acting on weighted Dirichlet spaces and determine the spectrum of a certain class of such operators. Our results extend…

Functional Analysis · Mathematics 2026-02-10 Anirban Sen

We obtain criteria for the boundedness and compactness of weighted composition operators between different Fock spaces in $\mathbb{C}^n$. We also give estimates for essential norm of these operators.

Complex Variables · Mathematics 2018-01-26 Pham Trong Tien , Le Hai Khoi

Two-side estimates for two-weighted discrete Hardy-type operators on a tree are obtained. For general weights we prove the discrete analogue of Evans - Harris - Pick theorem (it is a quite simple consequence from their result). It gives the…

Functional Analysis · Mathematics 2013-11-05 A. A. Vasil'eva

In this paper, a new characterization is provided for the boundedness, compactness and essential norm of the difference of two weighted composition operators on weighted-type spaces in the unit ball of $\mathbb{C}^n$.

Complex Variables · Mathematics 2018-04-12 Bingyang Hu , Songxiao Li