Differences of weighted composition operators between the Fock spaces

We study some important topological properties such as boundedness, compactness and essential norm of differences of weighted composition operators between Fock spacesComment: 10 page

Weighted composition operators between different Fock spaces

We study weighted composition operators acting between Fock spaces. The following results are obtained: (1) Criteria for the boundedness and compactness; (2) Characterizations of compact differences and essential norm; (3) Complete descriptions of path connected components and isolated points of the space of composition operators and the space of nonzero weighted composition operators

Frames and operators in Schatten classes

Let $T$ be a compact operator on a separable Hilbert space $H$. We show that, for $2\le p<\infty$, $T$ belongs to the Schatten class $S_p$ if and only if $\{\|Tf_n\|\}\in \ell^p$ for \emph{every} frame $\{f_n\}$ in $H$; and for $0<p\le2$, $T$ belongs to $S_p$ if and only if $\{\|Tf_n\|\}\in\ell^p$ for \emph{some} frame $\{f_n\}$ in $H$. Similar conditions are also obtained in terms of the sequence $\{\}$ and the double-indexed sequence $\{\}$.Comment: 27 page

SOME REMARKS ON THE SELF-ORGANIZING FEATURE MAPS

Joint Research on Environmental Science and Technology for the Eart