Operator Classes

  • Karl E. Gustafson
  • Duggirala K. M. Rao
Part of the Universitext book series (UTX)


The special properties of the numerical range of normal operators led to the creation of new operator classes. In particular, three classes of operators attracted a lot of attention. Each of these inherits one or more of the numerical range properties of the normal operator.


Spectral Radius Operator Class Quadratic Polynomial Numerical Range Bare Point 
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Notes and References

Notes and References for Section 6.1

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Notes and References for Section 6.3

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Notes and References for Section 6.6

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  3. K. Gustafson and D. Rao (1996). “Spectral States of Normal-like Operators,” to appear.Google Scholar

Copyright information

© Springer-Verlag New York, Inc. 1997

Authors and Affiliations

  • Karl E. Gustafson
    • 1
  • Duggirala K. M. Rao
    • 2
  1. 1.Department of MathematicsUniversity of Colorado at BoulderBoulderUSA
  2. 2.Department of MathematicsColegio Bolivar at CaliCaliColombia

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