2012/01/03 by Mate Matolcsi, Matolcsi, Mate, Imre Z. Ruzsa +3
Mathematics · #Combinatorics (math.CO) #FOS: Mathematics #math.CO
paper · pdf · doi:10.48550/arxiv.1201.0631
13 pages
arxiv created 2012/01/03 · arxiv updated 2012/01/04
We use combinatorial and Fourier analytic arguments to prove various non-existence results on systems of real and complex unbiased Hadamard matrices. In particular, we prove that a complete system of complex mutually unbiased Hadamard matrices (MUHs) in any dimension d cannot contain more than one real Hadamard matrix. We also give new proofs of several known structural results in low dimensions, for d≤ 6.