Czechoslovak Mathematical Journal, Vol. 70, No. 4, pp. 1091-1102, 2020
Main eigenvalues of real symmetric matrices with application to signed graphs
Zoran Stanić
Received March 29, 2019. Published online April 14, 2020.
Abstract: An eigenvalue of a real symmetric matrix is called main if there is an associated eigenvector not orthogonal to the all-1 vector $ j$. Main eigenvalues are frequently considered in the framework of simple undirected graphs. In this study we generalize some results and then apply them to signed graphs.
Keywords: main angle; signed graph; adjacency matrix; Laplacian matrix; Gram matrix
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Affiliations: Zoran Stanić, Faculty of Mathematics, University of Belgrade, Studentski trg 16, 11 000 Belgrade, Serbia, e-mail: zstanic@math.rs
