Previous |  Up |  Next

Article

Full entry | Fulltext not available (moving wall 24 months)      Feedback
Keywords:
Laplacian graph spectra; bipartite graph; spread of graph
Summary:
Let $G=(V,E)$, $V=\{v_1,v_2,\ldots ,v_n\}$, be a simple connected graph with $n$ vertices, $m$ edges and a sequence of vertex degrees $d_1\geq d_2\geq \cdots \geq d_n$. Denote by $A$ and $D$ the adjacency matrix and diagonal vertex degree matrix of $G$, respectively. The signless Laplacian of $G$ is defined as $L^+=D+A$ and the normalized signless Laplacian matrix as $\mathcal {L}^+=D^{-1/2}L^+ D^{-1/2}$. The normalized signless Laplacian spreads of a connected nonbipartite graph $G$ are defined as $r(G)= \gamma _{2}^{+}/ \gamma _{n}^{+}$ and $l(G)=\gamma _{2}^{+}-\gamma _{n}^{+}$, where $\gamma _1^+ \ge \gamma _2^+\ge \cdots \ge \gamma _n^+ \ge 0$ are eigenvalues of $\mathcal {L}^+$. We establish sharp lower and upper bounds for the normalized signless Laplacian spreads of connected graphs. In addition, we present a better lower bound on the signless Laplacian spread.
References:
[1] Andrade, E., Dahl, G., Leal, L., Robbiano, M.: New bounds for the signless Laplacian spread. Linear Algebra Appl. 566 (2019), 98-120. DOI 10.1016/j.laa.2018.12.019 | MR 3896162 | Zbl 1410.05114
[2] Andrade, E., Freitas, M. A. A. de, Robbiano, M., Rodríguez, J.: New lower bounds for the Randić spread. Linear Algebra Appl. 544 (2018), 254-272. DOI 10.1016/j.laa.2017.07.037 | MR 3765785 | Zbl 1388.05108
[3] Biernacki, M., Pidek, H., Ryll-Nardzewski, C.: Sur une inéqualité entre des intégrales definies. Ann. Univ. Mariae Curie-Skłodowska, Sect. A 4 (1950), 1-4 French. MR 0042474 | Zbl 0040.31904
[4] ndağ, Ş. B. Bozkurt Altı: Note on the sum of powers of normalized signless Laplacian eigenvalues of graphs. Math. Interdisc. Research 4 (2019), 171-182. DOI 10.22052/mir.2019.208991.1180
[5] ndağ, Ş. B. Bozkurt Altı: Sum of powers of normalized signless Laplacian eigenvalues and Randić (normalized) incidence energy of graphs. Bull. Int. Math. Virtual Inst. 11 (2021), 135-146. DOI 10.7251/BIMVI2101135A | MR 4187056 | Zbl 07540020
[6] Bozkurt, Ş. B., Güngör, A. D., Gutman, I., Çevik, A. S.: Randić matrix and Randić energy. MATCH Commun. Math. Comput. Chem. 64 (2010), 239-250. MR 2677585 | Zbl 1265.05113
[7] Butler, S. K.: Eigenvalues and Structures of Graphs: Ph.D. Thesis. University of California, San Diego (2008). MR 2711548
[8] Cavers, M., Fallat, S., Kirkland, S.: On the normalized Laplacian energy and general Randić index $R_{-1}$ of graphs. Linear Algebra Appl. 433 (2010), 172-190. DOI 10.1016/j.laa.2010.02.002 | MR 2645076 | Zbl 1217.05138
[9] Cheng, B., Liu, B.: The normalized incidence energy of a graph. Linear Algebra Appl. 438 (2013), 4510-4519. DOI 10.1016/j.laa.2013.01.003 | MR 3034547 | Zbl 1282.05104
[10] Chung, F. R. K.: Spectral Graph Theory. Regional Conference Series in Mathematics 92. AMS, Providence (1997). DOI 10.1090/cbms/092 | MR 1421568 | Zbl 0867.05046
[11] Cirtoaje, V.: The best lower bound depended on two fixed variables for Jensen's inequality with ordered variables. J. Inequal. Appl. 2010 (2010), Article ID 128258, 12 pages. DOI 10.1155/2010/128258 | MR 2749168 | Zbl 1204.26031
[12] Cvetković, D. M., Doob, M., Sachs, H.: Spectra of Graphs: Theory and Applications. Pure and Applied Mathematics 87. Academic Press, New York (1980). MR 0572262
[13] Cvetković, D., Rowlinson, P., Simić, S. K.: Signless Laplacian of finite graphs. Linear Algebra Appl. 423 (2007), 155-171. DOI 10.1016/j.laa.2007.01.009 | MR 2312332 | Zbl 1113.05061
[14] Cvetković, D., Simić, S. K.: Towards a spectral theory of graphs based on the signless Laplacian. II. Linear Algebra Appl. 432 (2010), 2257-2277. DOI 10.1016/j.laa.2009.05.020 | MR 2599858 | Zbl 1218.05089
[15] Das, K. C., Güngör, A. D., Bozkurt, Ş. B.: On the normalized Laplacian eigenvalues of graphs. Ars Comb. 118 (2015), 143-154. MR 3330443 | Zbl 1349.05205
[16] Gomes, H., Gutman, I., Martins, E. Andrade, Robbiano, M., Martín, B. San: On Randić spread. MATCH Commun. Math. Comput. Chem. 72 (2014), 249-266. MR 3241719 | Zbl 1464.05070
[17] Gomes, H., Martins, E., Robbiano, M., Martín, B. San: Upper bounds for Randić spread. MATCH Commun. Math. Comput. Chem. 72 (2014), 267-278. MR 3241720 | Zbl 1464.05236
[18] Gu, R., Huang, F., Li, X.: Randić incidence energy of graphs. Trans. Comb. 3 (2014), 1-9. DOI 10.22108/TOC.2014.5573 | MR 3239628 | Zbl 1463.05331
[19] Gutman, I., Milovanović, E., Milovanović, I.: Bounds for Laplacian-type graph energies. Miskolc Math. Notes 16 (2015), 195-203. DOI 10.18514/MMN.2015.1140 | MR 3384599 | Zbl 1340.05164
[20] Gutman, I., Trinajstić, N.: Graph theory and molecular orbitals: Total $\phi$-electron energy of alternant hydrocarbons. Chem. Phys. Lett. 17 (1972), 535-538. DOI 10.1016/0009-2614(72)85099-1
[21] Liu, B., Huang, Y., Feng, J.: A note on the Randić spectral radius. MATCH Commun. Math. Comput. Chem. 68 (2012), 913-916. MR 3052189 | Zbl 1289.05133
[22] Liu, M., Liu, B.: The signless Laplacian spread. Linear Algebra Appl. 432 (2010), 505-514. DOI 10.1016/j.laa.2009.08.025 | MR 2577696 | Zbl 1206.05064
[23] Güngör, A. D. Maden, Çevik, A. S., Habibi, N.: New bounds for the spread of the signless Laplacian spectrum. Math. Inequal. Appl. 17 (2014), 283-294. DOI 10.7153/mia-17-23 | MR 3220994 | Zbl 1408.05082
[24] Milovanović, I., Milovanović, E., Glogić, E.: On applications of Andrica-Badea and Nagy inequalities in spectral graph theory. Stud. Univ. Babeş-Bolyai, Math. 60 (2015), 603-609. MR 3437422 | Zbl 1389.05104
[25] Mitrinović, D. S.: Analytic Inequalities. Die Grundlehren der mathematischen Wissenschaften 165. Springer, Berlin (1970). DOI 10.1007/978-3-642-99970-3 | MR 274686 | Zbl 0199.38101
[26] Randić, M.: Characterization of molecular branching. J. Am. Chem. Soc. 97 (1975), 6609-6615. DOI 10.1021/ja00856a001
[27] Shi, L.: Bounds on Randić indices. Discrete Math. 309 (2009), 5238-5241. DOI 10.1016/j.disc.2009.03.036 | MR 2548924 | Zbl 1179.05039
[28] Zumstein, P.: Comparison of Spectral Methods Through the Adjacency Matrix and the Laplacian of a Graph: Diploma Thesis. ETH Zürich, Zürich (2005).
Partner of
EuDML logo