Research Article

Rayleigh-Quotient Representation of the Real Parts, Imaginary Parts, and Moduli of the Eigenvalues of General Matrices

Volume: 3 Number: 2 August 31, 2020
EN

Rayleigh-Quotient Representation of the Real Parts, Imaginary Parts, and Moduli of the Eigenvalues of General Matrices

Abstract

In the present paper, formulas for the Rayleigh-quotient representation of the real parts, imaginary parts, and moduli of the eigenvalues of general matrices are obtained that resemble corresponding formulas for the eigenvalues of self-adjoint matrices. These formulas are of interest in Linear Algebra and in the theory of linear dynamical systems. The key point is that a weighted scalar product is used that is defined by means of a special positive definite matrix. As applications, one obtains convexity properties of newly-defined numerical ranges of a matrix. A numerical example underpins the theoretical findings.

Keywords

Rayleigh quotient , Real and imaginary parts of eigenvalues , Moduli of eigenvalues , Asymptotic stability of dynamical systems , Circular damped eigenfrequencies

References

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APA
Kohaupt, L. (2020). Rayleigh-Quotient Representation of the Real Parts, Imaginary Parts, and Moduli of the Eigenvalues of General Matrices. Journal of Mathematical Sciences and Modelling, 3(2), 55-75. https://doi.org/10.33187/jmsm.669216
AMA
1.Kohaupt L. Rayleigh-Quotient Representation of the Real Parts, Imaginary Parts, and Moduli of the Eigenvalues of General Matrices. Journal of Mathematical Sciences and Modelling. 2020;3(2):55-75. doi:10.33187/jmsm.669216
Chicago
Kohaupt, Ludwig. 2020. “Rayleigh-Quotient Representation of the Real Parts, Imaginary Parts, and Moduli of the Eigenvalues of General Matrices”. Journal of Mathematical Sciences and Modelling 3 (2): 55-75. https://doi.org/10.33187/jmsm.669216.
EndNote
Kohaupt L (August 1, 2020) Rayleigh-Quotient Representation of the Real Parts, Imaginary Parts, and Moduli of the Eigenvalues of General Matrices. Journal of Mathematical Sciences and Modelling 3 2 55–75.
IEEE
[1]L. Kohaupt, “Rayleigh-Quotient Representation of the Real Parts, Imaginary Parts, and Moduli of the Eigenvalues of General Matrices”, Journal of Mathematical Sciences and Modelling, vol. 3, no. 2, pp. 55–75, Aug. 2020, doi: 10.33187/jmsm.669216.
ISNAD
Kohaupt, Ludwig. “Rayleigh-Quotient Representation of the Real Parts, Imaginary Parts, and Moduli of the Eigenvalues of General Matrices”. Journal of Mathematical Sciences and Modelling 3/2 (August 1, 2020): 55-75. https://doi.org/10.33187/jmsm.669216.
JAMA
1.Kohaupt L. Rayleigh-Quotient Representation of the Real Parts, Imaginary Parts, and Moduli of the Eigenvalues of General Matrices. Journal of Mathematical Sciences and Modelling. 2020;3:55–75.
MLA
Kohaupt, Ludwig. “Rayleigh-Quotient Representation of the Real Parts, Imaginary Parts, and Moduli of the Eigenvalues of General Matrices”. Journal of Mathematical Sciences and Modelling, vol. 3, no. 2, Aug. 2020, pp. 55-75, doi:10.33187/jmsm.669216.
Vancouver
1.Ludwig Kohaupt. Rayleigh-Quotient Representation of the Real Parts, Imaginary Parts, and Moduli of the Eigenvalues of General Matrices. Journal of Mathematical Sciences and Modelling. 2020 Aug. 1;3(2):55-7. doi:10.33187/jmsm.669216