@Article{Lo2020, author = "Lo, Ching-on and Wai-keung Loh, Anthony", title = "Hilbert-Schmidtness of weighted composition operators and their differences on Hardy spaces", journal = "Opuscula Math.", year = "2020", volume = "40", number = "4", pages = "495--507", doi = "https://doi.org/10.7494/OpMath.2020.40.4.495", url = "https://doi.org/10.7494/OpMath.2020.40.4.495", abstract = "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 \(H^2\).", keywords = "weighted composition operators, Hardy spaces, compact operators, Hilbert-Schmidt operators", issn = "1232-9274" }