Complex Hadamard matrices attached to even orthogonal schemes of class 4
Combinatorics
2016-12-06 v1
Abstract
A complex Hadamard matrix is a square matrix W with complex entries of absolute value 1 satisfying WW*=nI, where * stands for the Hermitian transpose and I is the identity matrix of order n. In this paper, we give constructions of complex Hadamard matrices in the Bose-Mesner algebra of a certain 4-class symmetric association scheme. Moreover, we determine the Nomura algebras to show that the resulting matrices are not decomposable into nontrivial generalized tensor products.
Keywords
Cite
@article{arxiv.1612.00926,
title = {Complex Hadamard matrices attached to even orthogonal schemes of class 4},
author = {Takuya Ikuta and Akihiro Munemasa},
journal= {arXiv preprint arXiv:1612.00926},
year = {2016}
}
Comments
16 pages. arXiv admin note: text overlap with arXiv:1411.0057