Krein Space Numerical Range of Block Matrices -- a Unified Approach to the Hyperbolic Case
Functional Analysis
2025-08-19 v1
Abstract
In this paper, we investigate the Krein space numerical range of -by- block matrices, with diagonal blocks as scalar multiples of the identity. For these matrices, we specifically investigate the cases when the respective boundary generating curves consist of hyperbolas. This provides a unified approach to derive established and new results concerning the numerical range hyperbolic shape.
Cite
@article{arxiv.2508.12039,
title = {Krein Space Numerical Range of Block Matrices -- a Unified Approach to the Hyperbolic Case},
author = {N. Bebiano and R. Lemos and G. Soares},
journal= {arXiv preprint arXiv:2508.12039},
year = {2025}
}