Abstract
The Laplacian spread of a graph is defined as the difference between the largest and second smallest eigenvalues of the Laplacian matrix of the graph. In this paper, bounds are obtained for the Laplacian spread of graphs. By the Laplacian spread, several upper bounds of the Nordhaus-Gaddum type of Laplacian eigenvalues are improved. Some operations on Laplacian spread are presented. Connected c-cyclic graphs with n vertices and Laplacian spread n − 1 are discussed.
Similar content being viewed by others
References
Y. H. Bao, Y. Y. Tan, Y. Z. Fan: The Laplacian spread of unicyclic graphs. Appl. Math. Lett. 22 (2009), 1011–1015.
Y. Chen, L. Wang: The Laplacian spread of tricyclic graphs. Electron. J. Comb. 16 (2009), R80.
D. M. Cvetković, M. Doob, H. Sachs: Spectra of Graphs. VEB Deutscher Verlag der Wissenschaften, Berlin, 1980.
K. C. Das: The Laplacian spectrum of a graph. Comput. Math. Appl. 48 (2004), 715–724.
E. R. van Dam, W. H. Haemers: Graphs with constant µ and {ie165-1}. Discrete Math. 182 (1998), 293–307.
Y. Z. Fan, J. Xu, Y. Wang, D. Liang: The Laplacian spread of a tree. Discrete Math. Theor. Comput. Sci. 10 (2008), 79–86. Electronic only.
Y. Fan, S. Li, Y. Tan: The Laplacian spread of bicyclic graphs. J. Math. Res. Expo. 30 (2010), 17–28.
M. Fiedler: Algebraic connectivity of graphs. Czech. Math. J. 23 (1973), 98–305.
F. Goldberg: Bounding the gap between extremal Laplacian eigenvalues of graphs. Linear Algebra Appl. 416 (2006), 68–74.
D. A. Gregory, D. Hershkowitz, S. J. Kirkland: The spread of the spectrum of a graph. Linear Algebra Appl. 332–334 (2001), 23–35.
R. Grone, R. Merris, V. S. Sunder: The Laplacian spectrum of a graph. SIAM J. Matrix Anal. Appl. 11 (1990), 218–239.
R. Grone, R. Merris: The Laplacian spectrum of a graph II. SIAM J. Discrete Math. 7 (1994), 221–229.
Y. Hong, J. L. Shu: A sharp upper bound for the spectral radius of the Nord- haus-Gaddum type. Discrete Math. 211 (2000), 229–232.
M. Lazić: On the Laplacian energy of a graph. Czech. Math. J. 56 (2006), 1207–1213.
J. Li, W. C. Shiu, W. H. Chan: Some results on the Laplacian eigenvalues of unicyclic graphs. Linear Algebra Appl. 430 (2009), 2080–2093.
P. Li, J. S. Shi, R. L. Li: Laplacian spread of bicyclic graphs. J. East China Norm. Univ. (Nat. Sci. Ed.) 1 (2010), 6–9. (In Chinese.)
H. Liu, M. Lu, F. Tian: On the Laplacian spectral radius of a graph. Linear Algebra Appl. 376 (2004), 135–141.
B. Liu, M. -H. Liu: On the spread of the spectrum of a graph. Discrete Math. 309 (2009), 2727–2732.
M. Lu, H. Liu, F. Tian: Laplacian spectral bounds for clique and independence numbers of graphs. J. Comb. Theory, Ser. B 97 (2007), 726–732.
R. Merris: Laplacian matrices of graphs: A survey. Linear Algebra Appl. 197–198 (1994), 143–176.
E. A. Nordhaus, J. W. Gaddum: On complementary graphs. Am. Math. Mon. 63 (1956), 175–177.
N. Ozeki: On the estimation of the inequality by the maximum. J. College Arts Chiba Univ. 5 (1968), 199–203.
L. Shi: Bounds on the (Laplacian) spectral radius of graphs. Linear Algebra Appl. 422 (2007), 755–770.
Z. You, B. Liu: The minimum Laplacian spread of unicyclic graphs. Linear Algebra Appl. 432 (2010), 499–504.
X. Zhang: On the two conjectures of Graffiti. Linear Algebra Appl. 385 (2004), 369–379.
B. Zhou: On sum of powers of the Laplacian eigenvalues of graphs. Linear Algebra Appl. 429 (2008), 2239–2246.
Author information
Authors and Affiliations
Corresponding author
Additional information
This work was supported by the NNSF of China (No. 11071088).
Rights and permissions
About this article
Cite this article
You, Z., Liu, B. The Laplacian spread of graphs. Czech Math J 62, 155–168 (2012). https://doi.org/10.1007/s10587-012-0003-z
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10587-012-0003-z