English
Related papers

Related papers: Compact differences of composition operators on we…

200 papers

As continuation of the study of polynomial approximation and composition operators on Dirichlet spaces of unit disk, which has settled a problem posed by Cima in 1976, the present paper aims to consider the case of the unbounded domains,…

Complex Variables · Mathematics 2022-02-25 Guangfu Cao , Haichou Li

In this paper, we prove that for every compact set of the unit disk of logarithmic capacity 0, there exists a Schur function both in the disk algebra and in the Dirichlet space such that the associated composition operator is in all…

Functional Analysis · Mathematics 2012-07-06 Pascal Lefèvre , Daniel Li , Hervé Queffélec , Luis Rodriguez-Piazza

We show that the decay of approximation numbers of compact composition operators on the Dirichlet space $\mathcal{D}$ can be as slow as we wish, which was left open in the cited work. We also prove the optimality of a result of…

Functional Analysis · Mathematics 2014-07-11 Daniel Li , Hervé Queffélec , Luis Rodriguez-Piazza

For $\alpha \in \mathbb{R}$, let $\mathscr{D}_\alpha$ denote the scale of Hilbert spaces consisting of Dirichlet series $f(s) = \sum_{n=1}^\infty a_n n^{-s}$ that satisfy $\sum_{n=1}^\infty |a_n|^2/[d(n)]^\alpha < \infty$. The…

Functional Analysis · Mathematics 2018-07-24 Maxime Bailleul , Ole Fredrik Brevig

In this paper, we introduce a discrete analogue of weighted Hardy spaces on rooted trees and study weighted composition operators between them in detail. In particular, we characterize bounded and compact weighted composition operators…

Functional Analysis · Mathematics 2021-12-16 P. Muthukumar , Ajay K. Sharma , Vivek Kumar

We study the complex symmetric structure of weighted composition--differentiation operators of order $n $ on the weighted Bergman spaces $A_{\alpha}^2$ with respect to some conjugations. Then we provide some examples of these operators.

Functional Analysis · Mathematics 2021-01-14 Mahbube Moradi , Mahsa Fatehi

We survey recent results about composition operators induced by analytic self-maps of the unit disk in the complex plane on various Banach spaces of analytic functions taking values in infinite-dimensional Banach spaces. We mostly…

Functional Analysis · Mathematics 2015-05-11 Jussi Laitila , Hans-Olav Tylli

In this paper, we consider the sum of weighted composition operator $C_{\psi_{0},\varphi_{0}}$ and the weighted composition--differentiation operator $D_{\psi_{n},\varphi_{n},n}$ on the Hardy and weighted Bergman spaces. We describe the…

Functional Analysis · Mathematics 2021-08-13 Mahsa Fatehi

We give a sufficient condition for a composition operator with positive characteristic to be compact on the Hardy space of Dirichlet series.

Functional Analysis · Mathematics 2024-02-21 Frédéric Bayart

We consider weighted composition operators, that is operators of the type $g \mapsto w \cdot g \circ f$, acting on spaces of Lipschitz functions. Bounded weighted composition operators, as well as some compact weighted composition…

Functional Analysis · Mathematics 2023-04-25 Arafat Abbar , Clément Coine , Colin Petitjean

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

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

A weighted composition operator on a reproducing kernel Hilbert space is given by a composition, followed by a multiplication. We study unitary and co-isometric weighted composition operators on unitarily invariant spaces on the Euclidean…

Functional Analysis · Mathematics 2025-12-23 Michael Hartz , Maximilian Tornes

Let $\varphi$ be a holomorphic self map of the bidisc that is Lipschitz on the closure. We show that the composition operator $C_{\varphi}$ is compact on the Bergman space if and only if $\varphi(\overline{\mathbb{D}^2})\cap…

Complex Variables · Mathematics 2025-07-22 Timothy G. Clos , Zeljko Cuckovic , Sonmez Sahutoglu

Every analytic self-map of the unit ball of a Hilbert space induces a bounded composition operator on the space of Bloch functions. Necessary and sufficient conditions for compactness of such composition operators are provided, as well as…

Functional Analysis · Mathematics 2017-04-05 Oscar Blasco , Pablo Galindo , Mikael Lindström , Alejandro Miralles

In this paper we investigate the following problem: when a bounded analytic function $\phi$ on the unit disk $\mathbb{D}$, fixing 0, is such that $\{\phi^n : n = 0, 1, 2, . . . \}$ is orthogonal in $\mathbb{D}$?, and consider the problem of…

Functional Analysis · Mathematics 2007-05-23 Gerardo A. Chacon , Gerardo R. Chacon , Jose Gimenez

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

In this paper, we consider composition operators on weighted Hilbert spaces of analytic functions and observe that a formula for the essential norm, give a Hilbert-Schmidt characterization and characterize the membership in Schatten-class…

Functional Analysis · Mathematics 2013-08-08 Mostafa Hassanlou

In this study we consider the approximation numbers of differences of composition operators acting on the Hardy-Hilbert space H 2 (D). We obtain both upper and lower bounds for these approximation numbers and by applying these general…

Functional Analysis · Mathematics 2025-09-25 Frédéric Bayart , Clifford Gilmore , Sibel Sahin

We study the composition operators on an algebra of Dirichlet series, the analogue of the Wiener algebra of absolutely convergent Taylor series, which we call the Wiener-Dirichlet algebra. The central issue is to understand the connection…

Functional Analysis · Mathematics 2009-04-17 Frédéric Bayart , Catherine Finet , Daniel Li , Hervé Queffélec