Contact Info
Combinatorics & Optimization
University of Waterloo
Waterloo, Ontario
Canada N2L 3G1
Phone: 519-888-4567, ext 33038
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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 LatoAbstract:
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}.