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arXiv · 1302.4757

The Schur-Horn theorem for operators with finite spectrum

Marcin Bownik·John Jasper
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Abstract

We characterize the set of diagonals of the unitary orbit of a self-adjoint operator with a finite spectrum. Our result extends the Schur-Horn theorem from a finite dimensional setting to an infinite dimensional Hilbert space analogous to Kadison's theorem for orthogonal projections and the second author's result for operators with three point spectrum.

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Marcin Bownik, John Jasper. 2013-02-19. The Schur-Horn theorem for operators with finite spectrum. https://arxiv.org/abs/1302.4757

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