Note on Laplacian energy of graphs

H.,Fath-Tabar, A. R.,Ashrafi, I.,Gutman

Let $G$ be an $(n,m)$-graph and $\mu_1,\mu_2,\ldots,\mu_n$ its Laplacian eigenvalues. The Laplacian energy $LE$ of $G$ is defined as $\sum\limits_{i=1}^n |\mu_i - 2m/n|$ . Some new bounds for $LE$ are presented, and some results from the paper B. Zhou, I. Gutman, Bull. Acad. Serbe Sci. Arts (Cl. Math. Natur.) bf 134 (2007) 1--11 are improved and extended.