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arXiv · 1812.06045

$k$-point semidefinite programming bounds for equiangular lines

David de Laat·Fabrício Caluza Machado·Fernando Mário de Oliveira Filho·Frank Vallentin
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Abstract

We give a hierarchy of $k$-point bounds extending the Delsarte-Goethals-Seidel linear programming $2$-point bound and the Bachoc-Vallentin semidefinite programming $3$-point bound for spherical codes. An optimized implementation of this hierarchy allows us to compute~$4$, $5$, and $6$-point bounds for the maximum number of equiangular lines in Euclidean space with a fixed common angle.

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David de Laat, Fabrício Caluza Machado, Fernando Mário de Oliveira Filho, Frank Vallentin. 2018-12-14. $k$-point semidefinite programming bounds for equiangular lines. https://doi.org/10.1007/s10107-021-01638-x

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