On the summation of absolute value of the eigenvalues of signed graphs

چکیده مقاله

Let G = (G;s) be a signed graph, where G = (V;E) is the underlying simple graph and s :E(G) to {-1, +1} is the sign function. In this paper we consider the spectral characterization of signed graphs. We obtain some lower bounds for summation of absolute value of the A- eigenvalues of signed graphs.