problems / kissing-5d

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Attack log — five-dimensional kissing number

2026-08-17 — start

Published record (fetched tonight)

Sources, all still stating 40≤τ5≤4440\le\tau_5\le 44:

Independently I will re-verify the four 40-point Gram bounds and the classical Levenshtein number 48 before claiming any comparison.

Plan

  1. Exact coordinates and Gram checks for D5,L5,Q5,R5D_5,L_5,Q_5,R_5.
  2. Exact Delsarte / restricted-distance LPs (rational Gegenbauer).
  3. Structural restrictions that can be certified exactly: codes containing a 24-cell, codes with only D5D_5 inner products, Q5-equator extensions.
  4. Search for an exact 41-point spherical code (algebraic ansätze, layer replacement). Numerical SDP without a positivity certificate is residue.

2026-08-17 — replay of the four 40-point codes

2026-08-17 — false start: add a 41st point to D5D_5

2026-08-17 — false start: complete the Q5Q_5 equator to a 24-cell

2026-08-17 — the D4-containing bound

2026-08-17 — restricted Delsarte, then exact duals

2026-08-17 — integer distance distributions for TD5T_{D_5}

2026-08-17 — construction residue

Published record we compare against

2026-08-27 — continue (q1)

2026-08-27 — polar vertices: all four codes are maximal

2026-08-27 — TQ5T_{Q_5} integer slice empty at N=44N=44

2026-08-27 — TL5T_{L_5} integer does not kill 41–43

2026-08-27 — A4A_4 extras and Szöllősi graph

2026-08-27 — continue (q2)

2026-08-27 — q2 results (no unrestricted move)

2026-08-27 — continue (q3)

2026-08-27 — q3 results (no unrestricted move)

2026-08-27 — q4 unrestricted dual hunt

2026-08-27 — q4 leftover graphs (no unrestricted move)

2026-08-27 — continue (q5)

2026-08-27 — q5 leftovers (interval unchanged so far)

2026-08-27 — continue (q6)

2026-08-27 — continue (q7)

2026-08-27 — continue (q8)

2026-08-29 — wrap (q8)