English
Related papers

Related papers: Numerical range of weighted composition operators …

200 papers

In this paper, we study the weighted compositon operators on weighted Bergman spaces of bounded symmetric domains. The necessary and sufficient conditions for a weighted composition operator $W_{\phi,\psi}$ to be bounded and compact are…

Functional Analysis · Mathematics 2007-07-16 Sanjay Kumar , Kanwar Jatinder Singh

Suppose $\varphi$ is a holomorphic self map of the unit disk and $C_\varphi$ is a composition operator with symbol $\varphi$ that fixes the origin and $0<|\varphi'(0)|<1$. This work explores sufficient conditions that ensure all holomorphic…

Complex Variables · Mathematics 2017-08-07 Bhupendra Paudyal

We investigate the compactness of composition operators on the Hardy space of Dirichlet series induced by a map $\varphi(s)=c_0s+\varphi_0(s)$, where $\varphi_0$ is a Dirichlet polynomial. Our results depend heavily on the characteristic…

Functional Analysis · Mathematics 2018-03-16 Frédéric Bayart , Ole Fredrik Brevig

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

In this paper we will show how the boundedness condition for the weighted composition operators on a class of spaces of analytic functions on the open right complex half-plane called Zen spaces (which include the Hardy spaces and weighted…

Functional Analysis · Mathematics 2017-02-09 Andrzej S. Kucik

We investigate the numerical ranges of weighted composition operators on weighted Dirichlet spaces, focusing on the properties of the inducing functions. We identify conditions on these functions under which the origin lies in the interior…

Functional Analysis · Mathematics 2026-02-11 Somdatta Barik , Anirban Sen , Kallol paul

Let $\phi(z)=(\phi_1(z),...,\phi_n(z))$ be a holomorphic self-map of $B_n$ and $\psi(z)$ a holomorphic function on $B_n$, and $H(B_n)$ the class of all holomorphic functions on $B_n$, where $B_n$ is the unit ball of $C^n$, the weight…

Functional Analysis · Mathematics 2013-12-30 Zhong-Shan Fang , Ze-Hua Zhou

Let {\phi} be an analytic self-map of D and be an analytic operator-valued function on D, where D is the unit disk. We provide necessary and sufficient conditions for the boundedness and compactness of weighted composition operators…

Functional Analysis · Mathematics 2016-04-22 Kobra Esmaeili

We characterize those pairs $(\psi,\varphi)$ of smooth mappings $\psi:\mathbb{R}^d\rightarrow\mathbb{C},\varphi:\mathbb{R}^d\rightarrow\mathbb{R}^d$ for which the corresponding weighted composition operator…

Functional Analysis · Mathematics 2024-11-12 Vicente Asensio , Enrique Jordá , Thomas Kalmes

In this paper, we consider \emph{unbounded} weighted composition operators acting on Fock space, and investigate some important properties of these operators, such as $\calC$-selfadjoint (with respect to weighted composition conjugations),…

Complex Variables · Mathematics 2018-11-27 Pham Viet Hai

We provide complete characterisations of nuclear weighted composition operators between two distinct $L^p(\mu)$-spaces, where $1\leq p<\infty$. As a consequence, when the underlying measure space is non-atomic, the only nuclear weighted…

Functional Analysis · Mathematics 2026-03-24 S. Al Ghafri , Y. Estaremi , S. Shamsigamchi

We obtain some estimates for norm and essential norm of the difference of two composition operators between weighted Bergman spaces $A^p_\alpha$ and $A^q_\beta$ on the unit ball. In particular, we completely characterize the boundedness and…

Complex Variables · Mathematics 2019-03-05 Yecheng Shi , Songxiao Li , Juntao Du

For holomorphic pairs of symbols $(u, \psi)$, we study various structures of the weighted composition operator $ W_{(u,\psi)} f= u \cdot f(\psi)$ defined on the Fock spaces $\mathcal{F}_p$. We have identified operators $W_{(u,\psi)}$ that…

Functional Analysis · Mathematics 2021-12-13 Werkaferahu Seyoum , Tesfa Mengestie

In this work we study the essential spectra of composition operators on weighted Bergman spaces of analytic functions which might be termed as "quasi-parabolic." This is the class of composition operators on $A_{\alpha}^{2}$ with symbols…

Functional Analysis · Mathematics 2018-03-01 Uğur Gül

In this paper, we investigate the normal weighed composition operators $W_{\psi,\varphi}$ which is $\mathcal{J}-$symmetric, $\mathcal{C}_1-$symmetric and $\mathcal{C}_2-$symmetric on the Hardy space $H^2(\mathbb{D})$ respectively. Firstly,…

Functional Analysis · Mathematics 2019-01-04 Hang Zhou , Ze-Hua Zhou

We give explicit descriptions of all path connected components and isolated points of both spaces of composition operators and nonzero weighted composition operators acting from a Fock space $\mathcal{F}^p(\mathbb{C}^n)$ to another one…

Complex Variables · Mathematics 2018-11-26 Pham Trong Tien , Le Hai Khoi

We first obtain a simpler proof of the main results in [IEOT, {\bf 93}(2021), 17], which characterized the bounded and compact differences $C_{u,\varphi}-C_{v,\psi}$ of two weighted composition operators acting from…

Functional Analysis · Mathematics 2025-07-29 Jiaoye Du , Cezhong Tong , Zicong Yang

A bounded linear operator $T$ on a separable complex Hilbert space $H$ is called $C$-normal if there is a conjugation $C$ on $H$ such that $ CT^\ast TC=TT^\ast$. Let $\varphi$ be a linear fractional self-map of $\mathbb{D}$. In this paper,…

Complex Variables · Mathematics 2022-04-18 Lian Hu , Songxiao Li , Rong Yang

When $\varphi$ and $\psi$ are linear-fractional self-maps of the unit ball $B_N$ in ${\mathbb C}^N$, $N\geq 1$, we show that the difference $C_{\varphi}-C_{\psi}$ cannot be non-trivially compact on either the Hardy space $H^2(B_N)$ or any…

Functional Analysis · Mathematics 2010-06-11 Katherine Heller , Barbara D. MacCluer , Rachel J. Weir

We obtain a complete description of semi-Fredholm spectra of operators of the form $(Tf)(z) = w(z)f(B(z)$ acting on the disc algebra in the case when $B$ is either elliptic or double parabolic finite Blaschke product of degree $d \geq 2$…

Spectral Theory · Mathematics 2025-05-13 Arkady Kitover , Mehmet Orhon