An independent exact recheck of a claimed finite counterexample to Gale's conjecture in R^3 (a recheck of a result by others)
Voronov (arXiv:2610.28828, 20 Oct 2026, unrefereed) claims a counterexample to Gale's conjecture βn,n+1 = βn+1(Bn) in R3: a set V of 101 points (Appendix A, seven decimals) with β4(V) > 0.88928 > β4(S2) = √((3+√3)/6) ≈ 0.88807. This is an independent recheck of a result by others. We claim nothing new and do not claim to have disproved Gale's conjecture. What was rechecked (Tier C: exact code, machine-checked certificates). The 303 appendix numbers give 101 distinct points; D2 = 100000021020030 (units 1e-14), attained by one pair; exactly 2030 pairs have distance > 0.88928 D, none on the threshold (weakest included ratio 0.8892809651, strongest excluded 0.8892597950; ratio margin 9.65e-7, so every coordinate set that rounds to Appendix A gives the same graph, and the author's 17-figure points give an identical edge set). The 2030-edge distance graph is not 4-colourable: DRAT and LRAT proofs verified by drat-trim, lrat-check.c and an independent Python LRAT checker, with a different encoder, solvers and checkers on the auditor's side, a corrupted-proof control, and positive and negative graph controls. It is 5-colourable, has a 425-edge edge-critical non-4-colourable subgraph, and β4(V) = 0.88928096513... exactly for the rounded set. The configuration is fragile: moving one coordinate by 1e-3 makes it 4-colourable in all 20 trials. Audit. A separate AI agent instance (not a human) reproduced these results with its own code (ACCEPT_WITH_CORRECTIONS; six corrections applied, including a tenfold error in the stated ratio margin). Limitations. The upper bound β4(B3) ≤ σ3 and Gale's wording are taken from the paper (Tier L); diam T = σ3 behind the bound is only sampled in floating point (Tier X). The step from non-4-colourability to β4(V) > 0.88928 is argued, not formalised; no Lean; no kissat run, no formally verified proof checker; dimensions 4-6 and the author's search code not examined; no human audit. The Appendix A coordinates, the PDF and the author's repository files are not redistributed (hashes and fetch instructions only).
Authors
- Xavier Callens
Publication Details
- Journal
- Zenodo (CERN European Organization for Nuclear Research)
- Published
- 2026-11-01
- DOI
- https://doi.org/10.5281/zenodo.23859705
- Primary Topic
- Limits and Structures in Graph Theory
- Type
- preprint