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The Numerical Range of 2-Dimensional Krein Space Operators

Published online by Cambridge University Press:  20 November 2018

Hiroshi Nakazato
Affiliation:
Department of Mathematical Sciences, Hirosaki University, 036-8561 Hirosaki, Japan e-mail: nakahr@cc.hirosaki-u.ac.jp
Natália Bebiano
Affiliation:
Mathematics Department, University of Coimbra, P 3000 Coimbra, Portugal e-mail: bebiano@mat.uc.pt
João da Providência
Affiliation:
Physics Department, University of Coimbra, P 3000 Coimbra, Portugal e-mail: providencia@teor.fis.uc.pt
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Abstract

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The tracial numerical range of operators on a 2-dimensional Krein space is investigated. Results in the vein of those obtained in the context of Hilbert spaces are obtained.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2008

References

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