ON THE SPECTRAL RADIUS, ENERGY AND ESTRADA INDEX OF THE SOMBOR MATRIX OF GRAPHS.

Let G be a simple undirected graph with vertex set V (G) = fv1, v2, .... vng and edge set E(G). The Sombor matrix S(G) of a graph G is defined so that its (i; j)-entry is equal to q d2i+ d2j if the vertices vi and vj are adjacent, and zero otherwise, where di denotes the degree of vertex vi in G. In this paper, lower and upper bounds on the spectral radius, energy and Estrada index of the Sombor matrix of graphs are obtained, and the respective extremal graphs are characterized. [ABSTRACT FROM AUTHOR]