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arXiv · 2307.16007

Inertia of Kwong matrices

Rajendra Bhatia·Tanvi Jain
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Abstract

Let $r$ be any real number and for any $n$ let $p_1,\ldots,p_n$ be distinct positive numbers. A Kwong matrix is the $n\times n$ matrix whose $(i,j)$ entry is $(p_i^r+p_j^r)/(p_i+p_j).$ We determine the signatures of eigenvalues of all such matrices. The corresponding problem for the family of Loewner matrices $\begin{bmatrix}(p_i^r-p_j^r)/(p_i-p_j)\end{bmatrix}$ has been solved earlier.

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Rajendra Bhatia, Tanvi Jain. 2023-07-29. Inertia of Kwong matrices. https://arxiv.org/abs/2307.16007

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