M-quasi-hyponormal composition operators

Abstract

A necessary and sufficient condition is obtained for M-quasi-hyponormal composition operators. It has also been proved that the class of M-quasi-hyponormal composition operators coincides with the class of M-paranormal composition operators. Existence of M-hyponormal composition operators which are not hyponormal; and M-quasihyponormal composition operators which are not M-hyponormal and quasi-hyponormal are also shown.

Keywords

• M-hyponormal
• M-quasi-hyponormal
• M-paranormal
• normal composition operators.