Open AccessHilbert-Schmidtness of weighted composition operators and their differences on Hardy spaces
Author(s) -
Ching-on Lo,
Anthony Wai-keung Loh
Publication year - 2020
Publication title -
rocznik akademii górniczo-hutniczej im. stanisława staszica. opuscula mathematica/opuscula mathematica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.481
H-Index - 16
eISSN - 2300-6919
pISSN - 1232-9274
DOI - 10.7494/opmath.2020.40.4.495
Subject(s) - mathematics , hardy space , hilbert space , composition (language) , composition operator , unit disk , space (punctuation) , combinatorics , operator (biology) , function (biology) , pure mathematics , multiplication operator , philosophy , linguistics , biochemistry , chemistry , repressor , evolutionary biology , biology , transcription factor , gene
Let \(u\) and \(\varphi\) be two analytic functions on the unit disk \(\mathbb{D}\) such that \(\varphi(\mathbb{D}) \subset \mathbb{D}\). A weighted composition operator \(uC_{\varphi}\) induced by \(u\) and \(\varphi\) is defined on \(H^2\), the Hardy space of \(\mathbb{D}\), by \(uC_{\varphi}f := u \cdot f \circ \varphi\) for every \(f\) in \(H^2\). We obtain sufficient conditions for Hilbert-Schmidtness of \(uC_{\varphi}\) on \(H^2\) in terms of function-theoretic properties of \(u\) and \(\varphi\). Moreover, we characterize Hilbert-Schmidt difference of two weighted composition operators on \(H^2\).