Two classes of $J$-operators

Document Type : Dedicated to Prof. A. T.-M. Lau


Hokkaido University (Emeritus), Sapporo, Japan


We define two classes ${\mathfrak A}$ and ${\mathfrak B}$ in the space ${\mathcal B}({\mathcal H})$ of operators acting on a Hilbert space on the basis of $J$-order relation and spectra, and discuss various properties related to these classes.


Main Subjects

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