{ "id": "2207.04599", "version": "v1", "published": "2022-07-11T03:10:49.000Z", "updated": "2022-07-11T03:10:49.000Z", "title": "A lower bound of the energy of non-singular graphs in terms of average degree", "authors": [ "Saieed Akbari", "Hossein Dabirian", "S. Mahmood Ghasemi" ], "categories": [ "math.CO" ], "abstract": "Let $G$ be a graph of order $n$ with adjacency matrix $A(G)$. The \\textit{energy} of graph $G$, denoted by $\\mathcal{E}(G)$, is defined as the sum of absolute value of eigenvalues of $A(G)$. It was conjectured that if $A(G)$ is non-singular, then $\\mathcal{E}(G)\\geq\\Delta(G)+\\delta(G)$. In this paper we propose a stronger conjecture as for $n \\geq 5$, $\\mathcal{E}(G)\\geq n-1+ d$, where $d$ is the average degree of $G$. Here, we show that conjecture holds for bipartite graphs, planar graphs and for the graphs with $d \\leq n-2\\ln n -3$", "revisions": [ { "version": "v1", "updated": "2022-07-11T03:10:49.000Z" } ], "analyses": { "keywords": [ "average degree", "lower bound", "non-singular graphs", "bipartite graphs", "conjecture holds" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }