The class of D(T)–operators on Hilbert space

Abdulwahid, Elaf S

doi:10.22075/ijnaa.2021.5645

The class of D(T)–operators on Hilbert space

Document Type : Research Paper

Author

Elaf S Abdulwahid

Tikrit University – College of Education for Women/ Department of Mathematics, Iraq

10.22075/ijnaa.2021.5645

Abstract

The purpose of this paper is to introduce a new class operator on separable Hilbert space. The operator T ∈ B(H) is called D(T)-operator if there exist U ∈ B(H), U≠0, I such that T^*TU = UT*T, where T* adjoint operator of T. Then, some main properties of the class of D(T)-operator are studied in this research.

Keywords

D(T)-operator

quasi-normal operator

The sepctrum of normal oprator

Hilbert space

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