مشخصات پژوهش

عنوان	On Linear Operators For Which $TT^D$ Is Normal
نوع پژوهش	مقاله چاپ‌شده در مجلات علمی
کلیدواژه‌ها	Drazin inverse‎, ‎Fuglede–Putnam theorem‎, ‎D-normal‎ ‎operators‎, ‎n-power D-normal operators
چکیده	‎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.
پژوهشگران	منصور دانا (نفر دوم)، رامش یوسفی (نفر اول)