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arXiv · 1705.05870

General explicit expressions for intertwining operators and direct rotations of two orthogonal projections

Yan-Ni Dou·Wei-Juan Shi·Miao-Miao Cui·Hong-Ke Du
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Abstract

In this paper, based on the block operator technique and operator spectral theory, the general explicit expressions for intertwining operators and direct rotations of two orthogonal projections have been established. As a consequence, it is an improvement of Kato's result (Perturbation Theory of Linear operators, Springer-Verlag, Berlin/Heidelberg, 1996); J. Avron, R. Seiler and B. Simon's Theorem 2.3 (The index of a pair of projections, J. Funct. Anal. 120(1994) 220-237) and C. Davis, W.M. Kahan, (The rotation of eigenvectors by a perturbation, III. SIAM J. Numer. Anal. 7(1970) 1-46).

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Yan-Ni Dou, Wei-Juan Shi, Miao-Miao Cui, Hong-Ke Du. 2017-05-16. General explicit expressions for intertwining operators and direct rotations of two orthogonal projections. https://arxiv.org/abs/1705.05870

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