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arXiv · 2412.10197

Quasi-orthogonal extension of symmetric matrices

Abderrahim Boussaïri·Brahim Chergui·Zaineb Sarir·Mohamed Zouagui
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Abstract

An $n\times n$ real matrix $Q$ is quasi-orthogonal if $Q^{\top}Q=qI_{n}$ for some positive real number $q$. If $M$ is a principal sub-matrix of a quasi-orthogonal matrix $Q$, we say that $Q$ is a quasi-orthogonal extension of $M$. In a recent work, the authors have investigated this notion for the class of real skew-symmetric matrices. Using a different approach, this paper addresses the case of symmetric matrices.

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Abderrahim Boussaïri, Brahim Chergui, Zaineb Sarir, Mohamed Zouagui. 2024-12-13. Quasi-orthogonal extension of symmetric matrices. https://arxiv.org/abs/2412.10197

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