论文信息 - A new relative bound for equiangular lines and nonexistence of tight spherical designs of harmonic index 4

A new relative bound for equiangular lines and nonexistence of tight spherical designs of harmonic index 4

We give a new upper bound for the cardinality of a set of equiangular lines in R n with a fixed common angle ? for each ( n , ? ) satisfying certain conditions. Our techniques are based on semidefinite programming methods for spherical codes introduced by Bachoc and Vallentin (2008). As a corollary to our bound, we show the nonexistence of spherical tight designs of harmonic index 4 on a sphere in R n with n ? 3 .

Wei-Hsuan Yu | Takayuki Okuda

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