Sums and products of symplectic eigenvalues

نویسندگان

چکیده

For every 2n×2n real positive definite matrix A, there exists a symplectic M such that MTAM=diag(D,D), where D is the n×n diagonal with entries d1(A)≤⋯≤dn(A). The numbers d1(A),…,dn(A) are called eigenvalues of A. We derive analogues Wielandt's extremal principle and multiplicative Lidskii's inequalities for eigenvalues.

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ژورنال

عنوان ژورنال: Linear Algebra and its Applications

سال: 2021

ISSN: ['1873-1856', '0024-3795']

DOI: https://doi.org/10.1016/j.laa.2021.08.016