English

Spectral Analysis for Non-Hermitian Matrices and Directed Graphs

Spectral Theory 2019-05-21 v3

Abstract

We generalize classical results in spectral graph theory and linear algebra more broadly, from the case where the underlying matrix is Hermitian to the case where it is non-Hermitian. New admissibility conditions are introduced to replace the Hermiticity condition. We prove new variational estimates of the Rayleigh quotient for non-Hermitian matrices. As an application, a new Delsarte-Hoffman-type bound on the size of the largest independent set in a directed graph is developed. Our techniques consist in quantifying the impact of breaking the Hermitian symmetry of a matrix and are broadly applicable.

Keywords

Cite

@article{arxiv.1812.04737,
  title  = {Spectral Analysis for Non-Hermitian Matrices and Directed Graphs},
  author = {Edinah K. Gnang and James M. Murphy},
  journal= {arXiv preprint arXiv:1812.04737},
  year   = {2019}
}
R2 v1 2026-06-23T06:39:40.858Z