TY - JOUR
T1 - On spectral spread and trace norm of Sombor matrix
AU - Rather, Bilal Ahmad
AU - Imran, Muhammad
AU - Diene, Adama
N1 - Publisher Copyright:
© 2024, The Indian National Science Academy.
PY - 2024
Y1 - 2024
N2 - For a simple graph G with vertex set { v1, ⋯ , vn} and degree sequence { d1, ⋯ , dn} , the Sombor matrix S(G) of G is an n× n matrix, whose (i, j) -th entry is di2+dj2 , if vi and vj are adjacent and 0, otherwise. The multi-set of the eigenvalues of S(G) is known as the Sombor spectrum of G, denoted by μ1≥ μ2≥ ⋯ ≥ μn , where μ1 is the Sombor spectral radius of G. The absolute sum of the Sombor eigenvalues is known as the trace norm (Sombor energy) of G. The spectral spread of S(G) is defined by s(S(G)) = μ1- μn . In this article, we establish various sharp bounds for s(S(G)) in terms of various graph parameters like order, Schatten norm, Frobenius norm, trace norm, Forgotten topological index, Sombor index and many other invariants. We give complete characterization of the extremal graphs attaining these bounds. As a consequence of s(S(G)) , we present the bounds on the trace norm of S(G) along with the graphs attaining them.
AB - For a simple graph G with vertex set { v1, ⋯ , vn} and degree sequence { d1, ⋯ , dn} , the Sombor matrix S(G) of G is an n× n matrix, whose (i, j) -th entry is di2+dj2 , if vi and vj are adjacent and 0, otherwise. The multi-set of the eigenvalues of S(G) is known as the Sombor spectrum of G, denoted by μ1≥ μ2≥ ⋯ ≥ μn , where μ1 is the Sombor spectral radius of G. The absolute sum of the Sombor eigenvalues is known as the trace norm (Sombor energy) of G. The spectral spread of S(G) is defined by s(S(G)) = μ1- μn . In this article, we establish various sharp bounds for s(S(G)) in terms of various graph parameters like order, Schatten norm, Frobenius norm, trace norm, Forgotten topological index, Sombor index and many other invariants. We give complete characterization of the extremal graphs attaining these bounds. As a consequence of s(S(G)) , we present the bounds on the trace norm of S(G) along with the graphs attaining them.
KW - Adjacency matrix
KW - Sombor index
KW - Sombor matrix
KW - spectral spread
KW - trace norm (energy)
UR - https://www.scopus.com/pages/publications/85181229980
UR - https://www.scopus.com/pages/publications/85181229980#tab=citedBy
U2 - 10.1007/s13226-023-00529-5
DO - 10.1007/s13226-023-00529-5
M3 - Article
AN - SCOPUS:85181229980
SN - 0019-5588
JO - Indian Journal of Pure and Applied Mathematics
JF - Indian Journal of Pure and Applied Mathematics
ER -