The Schur-horn Theorem for Operators with Finite Spectrum
نویسنده
چکیده
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 [17, 18], and the second author’s result for operators with three point spectrum [16].
منابع مشابه
Existence of frames with prescribed norms and frame operator
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