English

Matrices with invariant by rotation numerical ranges

Functional Analysis 2025-10-02 v2 Numerical Analysis Numerical Analysis

Abstract

We characterize the d x d matrices whose numerical ranges are invariant by rotations of angle 2π\pi/d.

Keywords

Cite

@article{arxiv.2507.20631,
  title  = {Matrices with invariant by rotation numerical ranges},
  author = {Michel Crouzeix},
  journal= {arXiv preprint arXiv:2507.20631},
  year   = {2025}
}
R2 v1 2026-07-01T04:21:44.566Z