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arXiv · 2110.02050

Eigenvalues and Singular Value Decomposition of Dual Complex Matrices

Liqun Qi·Ziyan Luo
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Abstract

We introduce right eigenvalues and subeigenvalues for square dual complex matrices. An $n \times n$ dual complex Hermitian matrix has exactly $n$ right eigenvalues and subeigenvalues, which are all real. The Hermitian matrix is positive semi-definite or definite if and only if all of its right eigenvalues and subeigenvalues are nonnegative or positive, respectively. A Hermitian matrix can be diagonalized if and only if it has no right subeigenvalues. Then we present the singular value decomposition for general dual complex matrices. The results are further extended to dual quaternion matrices.

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Liqun Qi, Ziyan Luo. 2021-10-05. Eigenvalues and Singular Value Decomposition of Dual Complex Matrices. https://arxiv.org/abs/2110.02050

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