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Numerical Ranges Arising from Simple Lie Algebras

Published online by Cambridge University Press:  20 November 2018

Chi-Kwong Li
Affiliation:
Department of Mathematics, College of William and Mary, P.O. Box 8795, Williamburg, VA 23187-8795, USA email: chkli@math.wm.edu website: http://www.math.wm.edu/~ckli
Tin-Yau Tam
Affiliation:
Department of Mathematics, Auburn University, Auburn, AL 36849-5310, USA email: tamtiny@mail.auburn.edu website: http://www.auburn.edu/~tamtiny
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Abstract

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A unified formulation is given to various generalizations of the classical numerical range including the $c$-numerical range, congruence numerical range, $q$-numerical range and von Neumann range. Attention is given to those cases having connections with classical simple real Lie algebras. Convexity and inclusion relation involving those generalized numerical ranges are investigated. The underlying geometry is emphasized.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2000

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