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arXiv · 2407.03164

Matrices with Hyperbolical Krein Space Numerical Range

N. Bebiano·R. Lemos·G. Soares
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Abstract

This paper is devoted to matrices with hyperbolical Krein space numerical range. This shape characterizes the 2-by-2 case and persists for certain classes of matrices, independently of their size. Ne\-cessary and sufficient conditions for low dimensional tridiagonal matrices to have this shape are obtained only involving the matrix entries

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N. Bebiano, R. Lemos, G. Soares. 2024-07-03. Matrices with Hyperbolical Krein Space Numerical Range. https://arxiv.org/abs/2407.03164

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