Generalized Rayleigh-Quotient Formulas for the Real Parts, Imaginary Parts, and Moduli of the Eigenvalues of General Matrices

Autor: Ludwig Kohaupt
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Universal Journal of Mathematics and Applications, Vol 4, Iss 1, Pp 9-25 (2021)
Druh dokumentu: article
ISSN: 2619-9653
Popis: In the present paper, generalized Rayleigh-quotient formulas for the real parts, imaginary parts, and moduli of the eigenvalues of general (not necessarily diagonalizable) matrices are derived by using quotients of the form $(Au,v)/(u,v)$ instead of $(Au,u)/(u,u)$. These formulas are new and correspond to similar formulas for diagonalizable matrices obtained recently. Numerical examples underpin the theoretical findings. We point out that, in the case of general matrices, the principal vectors of largest stage of matrix $A^{\ast}$ take over the role of the eigenvectors in the case of diagonalizable matrices. So, even though the formulas in both cases look very similar, the result is somehow unexpected and surprising.
Databáze: Directory of Open Access Journals