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arXiv · 1907.05817

Characterization of $k$-spectrally monomorphic Hermitian matrices

Kawtar Attas·Abderrahim Boussaïri·Imane Souktani
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Abstract

This paper solves the following problem about Hermitian matrices related to the theory of $2$-structures:\emph{ }Let $n$ be a positive integer and $k$ be an integer with $k\in \{3,\ldots,n-3\}$. Characterize the Hermitian matrices $A$ such that the characteristic polynomials of the $k\times k$ submatrices of $A$ are all equal. Such matrices are called $k$-spectrally monomorphic. A crucial step to obtain this characterization is proving that if a matrix $A$ is $k$-spectrally monomorphic then it is $l$-spectrally monomorphic for $l$ in $\{1,\ldots,min\{k, n-k\}\}$.

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Kawtar Attas, Abderrahim Boussaïri, Imane Souktani. 2019-07-12. Characterization of $k$-spectrally monomorphic Hermitian matrices. https://arxiv.org/abs/1907.05817

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