English

A complete characterization of graphs with exactly two positive eigenvalues

Combinatorics 2022-01-14 v3

Abstract

In 1977 Smith characterized graphs with exactly one positive eigenvalue. Since then, many particular results related to graphs with exactly two positive eigenvalues have emerged. In this paper we conclude this investigation by giving a full characterization of these graphs.

Cite

@article{arxiv.1805.09151,
  title  = {A complete characterization of graphs with exactly two positive eigenvalues},
  author = {Fang Duan and Qiongxiang Huang and Xueyi Huang and Zoran Stanić and Jianfeng Wang},
  journal= {arXiv preprint arXiv:1805.09151},
  year   = {2022}
}

Comments

19 pages, 7 figures

R2 v1 2026-06-23T02:05:43.191Z