Non-variational approximation of discrete eigenvalues of self-adjoint operators
نویسندگان
چکیده
منابع مشابه
Non-variational Approximation of Discrete Eigenvalues of Self-adjoint Operators
We establish sufficiency conditions in order to achieve approximation to discrete eigenvalues of self-adjoint operators in the second-order projection method suggested recently by Levitin and Shargorodsky, [15]. We find explicit estimates for the eigenvalue error and study in detail two concrete model examples. Our results show that, unlike the majority of the standard methods, second-order pro...
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For a self-adjoint linear operator with discrete spectrum or a Hermitian matrix the “extreme” eigenvalues define the boundaries of clusters in the spectrum of real eigenvalues. The outer extreme ones are the largest and the smallest eigenvalues. If there are extended intervals in the spectrum in which no eigenvalues are present, the eigenvalues bounding these gaps are the inner extreme eigenval...
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ژورنال
عنوان ژورنال: IMA Journal of Numerical Analysis
سال: 2007
ISSN: 1464-3642,0272-4979
DOI: 10.1093/imanum/drl015