DMGT

ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

https://doi.org/10.7151/dmgt

Discussiones Mathematicae Graph Theory

Journal Impact Factor (JIF 2022): 0.7

5-year Journal Impact Factor (2022): 0.7

CiteScore (2022): 1.9

SNIP (2022): 0.902

Discussiones Mathematicae Graph Theory

Article in press


Authors:

S. Pirzada

Shariefuddin Pirzada

Department of Math., University of Kashmir, Srinagar

email: pirzadasd@kashmiruniversity.ac.in

0000-0002-1137-517X

S. Khan

Saleem Khan

University of Kashmir

email: khansaleem1727@gmail.com

0000-0002-5966-8780

F. Belardo

Francesco Belardo

University of Naples Federico II

email: fbelardo@gmail.com

0000-0003-4253-2905

Title:

On the distribution of distance signless Laplacian eigenvalues with given independence and chromatic number

PDF

Source:

Discussiones Mathematicae Graph Theory

Received: 2022-11-12 , Revised: 2023-09-09 , Accepted: 2023-09-14 , Available online: 2023-10-19 , https://doi.org/10.7151/dmgt.2524

Abstract:

For a connected graph $G$ of order $n$, let $\mathcal {D}(G)$ be the distance matrix and $Tr(G)$ be the diagonal matrix of vertex transmissions of $G$. The distance signless Laplacian (dsL, for short) matrix of $G$ is defined as $\mathcal {D}^Q(G)=Tr(G)+\mathcal{D}(G)$, and the corresponding eigenvalues are the dsL eigenvalues of $G$. For an interval $I$, let $m_{\mathcal{D}^{Q}(G) } I$ denote the number of dsL eigenvalues of $G$ lying in the interval $I$. In this paper, for some prescribed interval $I$, we obtain bounds for $m_{\mathcal{D}^{Q}(G)}I$ in terms of the independence number $\alpha$ and the chromatic number $\chi$ of $G$. Furthermore, we provide lower bounds of $\partial_{1}^{Q}(G)$, the dsL spectral radius, for certain families of graphs in terms of the order $n$ and the independence number $\alpha$, or the chromatic number $\chi$.

Keywords:

distance matrix, distance signless Laplacian matrix, spectral radius, independence number, chromatic number

References:

  1. A. Alhevaz, M. Baghipur and E. Hashemi, On distance signless Laplacian spectrum and energy of graphs, Electron. J. Graph Theory Appl. (EJGTA) 6 (2018) 326–340.
    https://doi.org/10.5614/ejgta.2018.6.2.12
  2. M. Aouchiche and P. Hansen, Two Laplacians for the distance matrix of a graph, Linear Algebra Appl. 439 (2013) 21–33.
    https://doi.org/10.1016/j.laa.2013.02.030
  3. M. Aouchiche and P. Hansen, On the distance signless Laplacian of a graph, Linear Multilinear Algebra 64 (2016) 1113–1123.
    https://doi.org/10.1080/03081087.2015.1073215
  4. D. Cvetković, P. Rowlinson and S. Simić, An Introduction to the Theory of Graph Spectra (Cambridge Univ. Press, New York, 2009).
    https://doi.org/10.1017/CBO9780511801518
  5. K.C. Das, M. Aouchiche and P. Hansen, On distance Laplacian and distance signless Laplacian eigenvalues of graphs, Linear Multilinear Algebra 67 (2019) 2307–2324.
    https://doi.org/10.1080/03081087.2018.1491522
  6. K.C. Das, H. Lin and J. Guo, Distance signless Laplacian eigenvalues of graphs, Front. Math. China 14 (2019) 693–713.
    https://doi.org/10.1007/s11464-019-0779-3
  7. R.M. Karp, Reducibility among combinatorial problems, in: Complexity of Computer Computations, R.E. Miller, J.W. Thatcher and J.D. Bohlinger (Ed(s)), (Springer, Boston MA 1972) 85–103.
    https://doi.org/10.1007/978-1-4684-2001-2_9
  8. H. Lin and B. Zhou, The effect of graft transformations on distance signless Laplacian spectral radius, Linear Algebra Appl. 504 (2016) 433–461.
    https://doi.org/10.1016/j.laa.2016.04.020
  9. M. Marcus and H. Minc, A Survey of Matrix Theory and Matrix Inequalities, Reprint of the 1969 Edition (Dover Publications, New York, 1992).
  10. S. Pirzada, An Introduction to Graph Theory (Universities Press, Hyderabad, India, 2012).
  11. B.R. Rakshith, K.C. Das and M.A. Sriraj, On $($distance$)$ signless Laplacian spectra of graphs, J. Appl. Math. Comput. 67 (2021) 23–40.
    https://doi.org/10.1007/s12190-020-01468-8
  12. J. Xue, S. Liu and J. Shu, The complements of path and cycle are determined by their distance $($signless$)$ Laplacian spectra, Appl. Math. Comput. 328 (2018) 137–143.
    https://doi.org/10.1016/j.amc.2018.01.034
  13. L. You, L. Ren and G. Yu, Distance and distance signless Laplacian spread of connected graphs, Discrete Appl. Math. 223 (2017) 140–147.
    https://doi.org/10.1016/j.dam.2016.12.030
  14. L. You, M. Yang, W. So and W. Xi, On the spectrum of an equitable quotient matrix and its application, Linear Algebra Appl. 577 (2019) 21–40.
    https://doi.org/10.1016/j.laa.2019.04.013

Close