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arXiv · 0906.5056

Fredholm Perturbation of Spectra of $2\times 2$ Upper Triangular Matrix

Zhang Shifang·Zhong Huaijie·Wu Junde
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Abstract

As we knew, study the perturbation theory of spectra of operator is a very important project in mathematics physics, in particular, in quantum mechanics. In this paper, we characterize the Fredholm perturbation for the Weyl spectrum, essential spectrum, spectrum, left spectrum, right spectrum, lower semi-Fredholm spectrum, upper semi-Weyl spectrum and lower semi-Weyl spectrum of upper triangular operator matrix $M_{C}=({cc} A&C 0&B)$.

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Zhang Shifang, Zhong Huaijie, Wu Junde. 2009-06-27. Fredholm Perturbation of Spectra of $2\times 2$ Upper Triangular Matrix. https://arxiv.org/abs/0906.5056

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