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arXiv · 1612.05102

Self-interlacing polynomials II: Matrices with self-interlacing spectrum

Mikhail Tyaglov
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Abstract

An $n\times n$ matrix is said to have a self-interlacing spectrum if its eigenvalues $\lambda_k$, $k=1,\ldots,n$, are distributed as follows $$ \lambda_1>-\lambda_2>\lambda_3>\cdots>(-1)^{n-1}\lambda_n>0. $$ A method for constructing sign definite matrices with self-interlacing spectra from totally nonnegative ones is presented. We apply this method to bidiagonal and tridiagonal matrices. In particular, we generalize a result by O. Holtz on the spectrum of real symmetric anti-bidiagonal matrices with positive nonzero entries.

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Mikhail Tyaglov. 2016-12-05. Self-interlacing polynomials II: Matrices with self-interlacing spectrum. https://doi.org/10.13001/1081-3810.3453

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