Latin cubes of order $4$ and $4320$-point quaternionic constructions in ${\mathbb R}^{16}$

Rustem Takhanov

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arXiv · 2611.00927

Latin cubes of order $4$ and $4320$-point quaternionic constructions in ${\mathbb R}^{16}$

Rustem Takhanov

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Abstract

Possibly the most enduring lower-bound record for kissing numbers in dimensions greater than $8$ (excluding $24$) is $$ κ_{16}\geq 4320. $$ This lower bound is attained by a shell of the famous Barnes--Wall lattice, which was discovered in 1959. Besides this configuration, at least one alternative $4320$-point kissing arrangement is currently known. Recently, it was noticed that all these configurations can be described in terms of the so-called quaternionic construction, a general type of construction that was instrumental in explaining the geometry of the $841$-point kissing arrangement in ${\mathbb R}^{12}$. We give a simple generalization of quaternionic constructions in ${\mathbb R}^{16}$ obtained from record configurations. They are parameterized by three Latin cubes of order $4$, six permutations of $3$-element set, and are all infinitesimally jammed. Computer-aided counting shows that there are $4\,072\,728\,621$ isometry classes in this family of $4320$-point kissing arrangements.

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Rustem Takhanov. 2026-10-31. Latin cubes of order $4$ and $4320$-point quaternionic constructions in ${\mathbb R}^{16}$. https://arxiv.org/abs/2611.00927

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