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arXiv · 1811.04181

Upper semi-Weyl and upper semi-Browder spectra of unbounded upper triangular operator matrices

Wurichaihu Bai·Qingmei Bai·Alatancang Chen
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Abstract

In this paper, we study the unbounded upper triangular operator matrix with diagonal domain. Some sufficient and necessary conditions are given under which upper semi-Weyl spectrum (resp. upper semi-Browder spectrum) of such operator matrix is equal to the union of the upper semi-Weyl spectra (resp. the upper semi-Browder spectra) of its diagonal entries. As an application, the corresponding spectral properties of Hamiltonian operator matrix are obtained.

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Wurichaihu Bai, Qingmei Bai, Alatancang Chen. 2018-11-10. Upper semi-Weyl and upper semi-Browder spectra of unbounded upper triangular operator matrices. https://arxiv.org/abs/1811.04181

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