# Equiangular lines in Euclidean spaces

@article{Greaves2016EquiangularLI,
title={Equiangular lines in Euclidean spaces},
author={Gary R. W. Greaves and Jacobus H. Koolen and Akihiro Munemasa and Ferenc Sz{\"o}ll{\"o}si},
journal={J. Comb. Theory, Ser. A},
year={2016},
volume={138},
pages={208-235}
}
We obtain several new results contributing to the theory of real equiangular line systems. Among other things, we present a new general lower bound on the maximum number of equiangular lines in d dimensional Euclidean space; we describe the two-graphs on 12 vertices; and we investigate Seidel matrices with exactly three distinct eigenvalues. As a result, we improve on two long-standing upper bounds regarding the maximum number of equiangular lines in dimensions d = 14 and d = 16 . Additionally… Expand

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