Laplacian energy of a graph
نویسندگان
چکیده
Let G be a graph with n vertices and m edges. Let λ1, λ2, . . . , λn be the eigenvalues of the adjacency matrix of G, and let μ1, μ2, . . . , μn be the eigenvalues of the Laplacian matrix of G. An earlier much studied quantity E(G) = ∑ni=1 |λi | is the energy of the graph G. We now define and investigate the Laplacian energy as LE(G) = ∑ni=1 |μi − 2m/n|. There is a great deal of analogy between the properties of E(G) and LE(G), but also some significant differences. © 2005 Elsevier Inc. All rights reserved. AMS classification: 05C50; 15A18; 05C90
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