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arXiv · 1602.08435

Thompson's theorem for compact operators and diagonals of unitary operators

John Jasper·Jireh Loreaux·Gary Weiss
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Abstract

As applications of Kadison's Pythageorean and carpenter's theorems, the Schur-Horn theorem, and Thompson's theorem, we obtain an extension of Thompsons theorem to compact operators and use these ideas to give a characterization of diagonals of unitary operators. Thompson's mysterious inequality concerning the last terms of the diagonal and singular value sequences plays a central role.

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John Jasper, Jireh Loreaux, Gary Weiss. 2016-02-26. Thompson's theorem for compact operators and diagonals of unitary operators. https://doi.org/10.1512/iumj.2018.67.6291

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