A Fourier Consequence for Lattice Kissing Numbers and Average Contacts

A mix of human-written and AI-generated textHuman understanding: all partsmath.MG — Metric Geometrymath.CO — Combinatoricsmath.NT — Number Theory

Contributed by Scott Kominers ↗

SubmitterScott Kominers

Version 1 / Oct 02, 2026 / CC BY-SA 4.0

Abstract

We deduce a new asymptotic upper bound Klat(n)≤(2e/π+o(1))nK_{\mathrm{lat}}(n)\leq\left(\sqrt{2e/\pi}+o(1)\right)^n on the maximal lattice kissing number Klat(n)K_{\mathrm{lat}}(n) in dimension nn, using the explicit auxiliary functions constructed in OpenAI's "Ten Advances" preprint. The same bound holds for the average contact degree of a finite packing of congruent balls. The bound's base-22 exponential rate rounds to 0.39560.3956, matching the value extrapolated empirically by Afkhami-Jeddi, Cohn, Hartman, de Laat, and Tajdini in 2020.

Provenance statement

I used LLMs to assist with analysis and synthesis in the preparation of this article, particularly GPT-6 Astra and Claude Fable 5.1 (accessed in part via Poe with the support of Quora, where I am an advisor). In particular, the bound I present was developed in dialogue with GPT-6 Astra. In addition, I greatly appreciate helpful comments from Henry Cohn and Thijs Laarhoven.

Tools used

OpenAI
GPTVersion 6 Astra
Anthropic
Claude FableVersion 5.1
Quora
Poe

References

  1. Nima Afkhami-Jeddi, Henry Cohn, Thomas Hartman, David de Laat, and Amirhossein Tajdini, High-dimensional sphere packing and the modular bootstrap , J. High Energy Phys. 2020 (2020), no. 12, 066, https://doi.org/10.1007/JHEP12(2020)066 doi:10.1007/JHEP12(2020)066 .DOI
  2. Kurt M. Anstreicher, Improved linear programming bounds for antipodal spherical codes , Discrete Comput. Geom. 28 (2002), no. 1, 107--114, https://doi.org/10.1007/s00454-001-0080-5 doi:10.1007/s00454-001-0080-5 .DOI
  3. E. S. Barnes and G. E. Wall, Some extreme forms defined in terms of Abelian groups , J. Austral. Math. Soc. 1 (1959), no. 1, 47--63, https://doi.org/10.1017/S1446788700025064 doi:10.1017/S1446788700025064 .DOI
  4. Huck Bennett, Alexander Golovnev, and Noah Stephens-Davidowitz, Difficulties constructing lattices with exponential kissing number from codes , IEEE Trans. Inform. Theory 71 (2025), no. 10, 7644--7648, https://doi.org/10.1109/TIT.2025.3593195 doi:10.1109/TIT.2025.3593195 .DOI
  5. K \'a roly Bezdek and Muhammad A. Khan, Contact numbers for sphere packings , New Trends in Intuitive Geometry , Bolyai Soc. Math. Stud., vol. 27, Springer, Berlin, Heidelberg, 2018, https://doi.org/10.1007/978-3-662-57413-3_2 doi:10.1007/978-3-662-57413-3_2 , pp. 25--47.DOI
  6. Henry Cohn and Noam Elkies, New upper bounds on sphere packings I , Ann. of Math. (2) 157 (2003), no. 2, 689--714, https://doi.org/10.4007/annals.2003.157.689 doi:10.4007/annals.2003.157.689 .DOI
  7. Henry Cohn and Yufei Zhao, Sphere packing bounds via spherical codes , Duke Math. J. 163 (2014), no. 10, 1965--2002, https://doi.org/10.1215/00127094-2738857 doi:10.1215/00127094-2738857 .DOI
  8. P. Delsarte, J. M. Goethals, and J. J. Seidel, Spherical codes and designs , Geom. Dedicata 6 (1977), no. 3, 363--388, https://doi.org/10.1007/BF03187604 doi:10.1007/BF03187604 .DOI
  9. Maria Dostert, Alexander Kolpakov, and Fernando M \'a rio de Oliveira Filho, Semidefinite programming bounds for the average kissing number , Israel J. Math. 247 (2022), no. 2, 635--659, https://doi.org/10.1007/s11856-022-2288-4 doi:10.1007/s11856-022-2288-4 .DOI
  10. Maxime Fortier Bourque and Bram Petri, Kissing numbers of closed hyperbolic manifolds , Amer. J. Math. 144 (2022), no. 4, 1067--1085, https://doi.org/10.1353/ajm.2022.0023 doi:10.1353/ajm.2022.0023 .DOI
  11. D. V. Gorbachev, Extremal problem for entire functions of exponential spherical type, connected with the Levenshtein bound on the sphere packing density in $ R ^n$ , Izv. Tul. Gos. Univ. Ser. Mat. Mekh. Inform. 6 (2000), no. 1, 71--78 (Russian).
  12. G. A. Kabatiansky and V. I. Levenshtein, On bounds for packings on a sphere and in space , Problems Inform. Transmission 14 (1978), no. 1, 1--17.
  13. Thijs Laarhoven and Scott Duke Kominers, A lattice family with kissing numbers $ ( L _n) e^ 2 n $ , https://arxiv.org/abs/2609.13608v2 arXiv:2609.13608v2 , 2026.arXiv
  14. Gabriele Nebe, The second minimum of Barnes--Wall lattices , https://arxiv.org/abs/2603.23133v2 arXiv:2603.23133v2 , 2026.arXiv
  15. OpenAI , Ten advances in mathematics and theoretical computer science , 2026, technical manuscript, version of August 6, 2026. https://cdn.openai.com/pdf/ten-proofs-oai.pdf (accessed September 26, 2026).link
  16. Alex Samorodnitsky, On linear programming bounds for spherical codes and designs , Discrete Comput. Geom. 31 (2004), no. 3, 385--394, https://doi.org/10.1007/s00454-003-2858-0 doi:10.1007/s00454-003-2858-0 .DOI
  17. Naser Talebizadeh Sardari and Masoud Zargar, New upper bounds for spherical codes and packings , Math. Ann. 389 (2024), 3653--3703, https://doi.org/10.1007/s00208-023-02738-z doi:10.1007/s00208-023-02738-z .DOI
  18. V. M. Sidel'nikov, New bounds for densest packing of spheres in $n$ -dimensional Euclidean space , Math. USSR-Sb. 24 (1974), no. 1, 147--157, https://doi.org/10.1070/SM1974v024n01ABEH001911 doi:10.1070/SM1974v024n01ABEH001911 .DOI
  19. Nils-Peter Skoruppa, Quick asymptotic upper bounds for lattice kissing numbers , Mathematika 49 (2002), no. 1--2, 51--57, https://doi.org/10.1112/S0025579300016041 doi:10.1112/S0025579300016041 .DOI
  20. Serge Vl a du t , Lattices with exponentially large kissing numbers , Mosc. J. Comb. Number Theory 8 (2019), no. 2, 163--177, retracted in 2025.
  21. G. L. Watson, The number of minimum points of a positive quadratic form , Dissertationes Math. (Rozprawy Mat.), no. 84, Instytut Matematyczny Polskiej Akademii Nauk, Warszawa, 1971.
  22. Masoud Zargar, Stiefel manifolds and upper bounds for spherical codes and packings , https://arxiv.org/abs/2407.10697 arXiv:2407.10697 , 2024.arXiv

Version history

  1. v1Initial depositCurrentOct 02, 2026