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Mansour Dana

Mansour Dana

Academic rank: Associate Professor
ORCID:
Education: PhD.
ScopusId: 14043156700
HIndex:
Faculty: Faculty of Science
Address:
Phone:

Research

Title
On Linear Operators For Which $TT^D$ Is Normal
Type
JournalPaper
Keywords
Drazin inverse‎, ‎Fuglede–Putnam theorem‎, ‎D-normal‎ ‎operators‎, ‎n-power D-normal operators
Year
2019
Journal FILOMAT
DOI
Researchers Ramesh Yousefi ، Mansour Dana

Abstract

‎A Drazin invertible operator $T \in \mathcal{B}(\mathcal{H})$ is called skew D-quasi-normal operator if $T^*$ and $TT^D$ commute or equivalently $TT^D$ is normal‎. ‎In this paper‎, ‎firstly we give a list of conditions on an operator $T,$ each of‎ ‎which is equivalent to $T$ being skew D-quasi-normal‎. ‎Furthermore‎, ‎we obtain the matrix‎ ‎representation of these operators‎. ‎We also develop some basic properties of‎ ‎such operators‎. ‎Secondly we extend the Kaplansky theorem and the Fuglede-Putnam commutativity theorem for normal‎ ‎operators to skew D-quasi-normal matrices‎.