2011/06/03 by Farber, Miriam, Kaminer, Ido
#Combinatorics (math.CO) #FOS: Mathematics
paper · doi:10.48550/arxiv.1106.0769
In this note we give a new upper bound for the Laplacian eigenvalues of an unweighted graph. Let G be a simple graph on n vertices. Let dm(G) and λm+1(G) be the m-th smallest degree of G and the m+1-th smallest Laplacian eigenvalue of G respectively. Then λm+1(G)≤ dm(G)+m-1 for G ≠ Km+(n-m)K1 . We also introduce upper and lower bound for the Laplacian eigenvalues of weighted graphs, and compare it with the special case of unweighted graphs.