Equiangular lines in low dimensional Euclidean spaces

19 Feb 2020 · Greaves Gary R. W., Syatriadi Jeven, Yatsyna Pavlo ·

We show that the maximum cardinality of an equiangular line system in 14 and 16 dimensions is 28 and 40, respectively, thereby solving a longstanding open problem. We also improve the upper bounds on the cardinality of equiangular line systems in 19 and 20 dimensions to 74 and 94, respectively.