Monday, January 31, 2022

Monday, January 31, 2022 — 11:30 to 11:30 AM EST

Title: Hadamard diagonalizable graphs of small order

Speaker: Steve Butler Affiliation: Iowa State University Zoom: Contact Sabrina Lato

Abstract:

A graph whose Laplacian matrix has a full set of eigenvectors with entries in {1,-1} is said to be Hadamard diagonalizable (i.e. there exists a Hadamard matrix which diagonalizes the Laplacian matrix). We demonstrate that the only diagonalizable graphs on n=8k+4 vertices are K_n and K_{n/2,n/2}.

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