On Hermitian Adjacency Matrices for Mixed Graphs

التفاصيل البيبلوغرافية
العنوان: On Hermitian Adjacency Matrices for Mixed Graphs
المؤلفون: She, Tao, Wang, Chunxiang
سنة النشر: 2022
المجموعة: Mathematics
مصطلحات موضوعية: Mathematics - Combinatorics, 05C50, 15A18
الوصف: We study the spectra of mixed graphs about its Hermitian adjacency matrix of the second kind (i.e. N-matrix) introduced by Mohar [1]. We extend some results and define one new Hermitian adjacency matrix, and the entry corresponding to an arc from $u$ to $v$ is equal to the $k$-th( or the third) root of unity, i.e. ${\omega} = cos(2{\pi}/k) + \textbf{i} \ sin(2{\pi}/k), k {\geq} 3$; the entry corresponding to an undirected edge is equal to 1, and 0 otherwise. In this paper, we characterize the cospectrality conditions for a mixed graph and its underlying graph. In section 4, we determine a sharp upper bound on the spectral radius of mixed graphs, and provide the corresponding extremal graphs.
Comment: 14 pages, 5 figures
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2205.15584
رقم الأكسشن: edsarx.2205.15584
قاعدة البيانات: arXiv