Diagonals of Self-adjoint Operators with Finite Spectrum
نویسنده
چکیده
Given a finite set X ⊆ R we characterize the diagonals of self-adjoint operators with spectrum X. Our result extends the SchurHorn theorem from a finite dimensional setting to an infinite dimensional Hilbert space analogous to Kadison’s theorem for orthogonal projections [8, 9] and the second author’s result for operators with three point spectrum [7].
منابع مشابه
The Schur-horn Theorem for Operators with Finite Spectrum
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].
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