Abstract
For a simple connected graph G of order n and size m, the Laplacian energy of G is defined as LE(G) = Sigma(n)(i=1) vertical bar mu(i) - 2m/n vertical bar where mu(1), mu(2), ... , mu(n-1), mu(n) are the Laplacian eigenvalues of G satisfying mu(1) >= mu(2) >= ... >= mu(n-1) > mu(n) = 0. In this note, some new lower bounds on the graph invariant LE(G) are derived. The obtained results are compared with some already known lower bounds of LE(G).