Pseudo-spectrum and Numerical Range of Matrices Walker of Dimension Three

Abstract

The study of numerical range, spectrum and pseudo spectrum appears in diffrent sci- entific fields, for example the domain of spectral theory, the stability of dynamics elec- tricity, physics, the quantum mechanics. In this paper, we find the spectrum, pseudo- spectrum and numerical range on Walker manifolds of dimension three. Two examples are given for metric g f .

Keywords

• Bounded operator
• Spectrum
• Pseudo-spectrum
• Numerical range
• Matrix Walker.

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