Integral Equations and Operator Theory

, Volume 36, Issue 1, pp 1–10 | Cite as

ω-Hyponormal operators

  • Ariyadasa Aluthge
  • Derming Wang


The class of ω-hyponormal operators is introduced. This class contains allp-hyponormal operators. Certain properties of this class of operators are obtained. Among other things, it is shown that ifT is ω-hyponormal, then its spectral radius and norm are identical, and the nonzero points of its joint point spectrum and point spectrum are identical. Conditions under which a ω-hyponormal operator becomes normal, self-adjoint and unitary are given.

AMS Classification

47N20 47A30 47B15 


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Copyright information

© Birkhäuser Verlag 2000

Authors and Affiliations

  • Ariyadasa Aluthge
    • 1
  • Derming Wang
    • 2
  1. 1.Department of MathematicsMarshall UniversityHuntington
  2. 2.Department of MathematicsCalifornia State University, Long BeachLong Beach

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