Applications of the joint angular field of values

Author:
George Phillip Barker

Journal:
Proc. Amer. Math. Soc. **91** (1984), 331-335

MSC:
Primary 15A60

DOI:
https://doi.org/10.1090/S0002-9939-1984-0744623-X

MathSciNet review:
744623

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Abstract: Let be hermitian matrices and let be the real space of hermitian matrices. If , then the extreme rays of the joint angular field of values of are determined. Then this cone is used to give necessary and sufficient conditions for the existence of hermitian matrices such that preserves the cone of the positive semidefinite matrices where is the dyad product .

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Additional Information

DOI:
https://doi.org/10.1090/S0002-9939-1984-0744623-X

Keywords:
Numerical range,
positive semidefinite matrices,
linear transformations of hermitian matrices

Article copyright:
© Copyright 1984
American Mathematical Society