A complete characterization of graphs with exactly two positive eigenvalues

2018/05/21 by Fang Duan, Qiongxiang Huang, Duan, Fang +7
Chemistry · Materials Science · Mathematics · #05C50 #Combinatorics (math.CO) #FOS: Mathematics #Graph theory and applications #Synthesis and Properties of Aromatic Compounds #Synthesis and properties of polymers

paper · pdf · doi:10.48550/arxiv.1805.09151

openalex publication_date 2018/05/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

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.

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