Finite and infinite dimensional generalizations of Klyachko theorem
نویسنده
چکیده
We describe the convex set of the eigenvalues of hermitian matrices which are majorized by sum of m hermitian matrices with prescribed eigenvalues. We extend our characterization to selfadjoint nonnegative (definite) compact operators on a separable Hilbert space. We give necessary and sufficient conditions on the eigenvalue sequence of a selfadjoint nonnegative compact operator of trace class to be a sum of m selfadjoint nonnegative compact operators of trace class with prescribed eigenvalue sequences.
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