On a New Class of Generalized Normal Operators

  • M. DanaEmail author
  • R. Yousefi


In this paper we introduce and analyze a new class of generalized normal operators, namely skew D-quasi-normal operators, for a bounded linear operator T on a Hilbert space \(\mathcal {H}\) using the Drazin \(T^D\) inverse of T. After establishing the basic properties of such operators, we give examples and discuss how this class of operators is distinct from several other operator classes. We also generalize a very famous result on normal operators, due to Fuglede.


Drazin inverse N-normal operators D-normal operators D-quasi-normal operators 

Mathematics Subject Classification

47B15 47B20 47A15 15A09 



The authors would like to thank the referees for their valuable comments and suggestions, which allowed improving considerably the writing of the paper.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Faculty of MathematicsUniversity of KurdistanSanandajIslamic Republic of Iran

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