Complex Hadamard Matrices and Combinatorial Structures
نویسنده
چکیده
Forty years ago, Goethals and Seidel showed that if the adjacency algebra of a strongly regular graph X contains a Hadamard matrix then X is of Latin square type or of negative Latin square type [8]. We extend their result to complex Hadamard matrices and find only three additional families of parameters for which the strongly regular graphs have complex Hadamard matrices in their adjacency algebras. We see that there are only three distance regular covers of complete graphs that give complex Hadamard matrices.
منابع مشابه
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