Nodal domain and eigenvalue multiplicity of graphs
نویسندگان
چکیده
Let G = (V,E) be a graph with vertex set V = {1, . . . , n} and edge set E. Throughout the paper, a graph G is undirected and simple (i.e., has no multi-edges or loops). We allow G to be disconnected. The Laplacian of G is the matrix L(G) = D−A, where D is the diagonal matrix whose entries are the degree of the vertices and A is the adjacency matrix of G. Chung’s normalized Laplacian L̃(G) [6] is defined by
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