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
Classification MSC:  05C22, 05C50


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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


 
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