Bordered complex Hadamard matrices and strongly regular graphs
Combinatorics
2020-11-19 v4
Abstract
We consider bordered complex Hadamard matrices whose core is contained in the Bose-Mesner algebra of a strongly regular graph. Examples include a complex Hadamard matrix whose core is contained in the Bose-Mesner algebra of a conference graph due to J. Wallis, F. Sz\"{o}ll\H{o}si, and a family of Hadamard matrices given by Singh and Dubey. In this paper, we prove that there are no other bordered complex Hadamard matrices whose core is contained in the Bose-Mesner algebra of a strongly regular graph.
Cite
@article{arxiv.2008.00609,
title = {Bordered complex Hadamard matrices and strongly regular graphs},
author = {Takuya Ikuta and Akihiro Munemasa},
journal= {arXiv preprint arXiv:2008.00609},
year = {2020}
}
Comments
21 pages, corrected typo