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Science & mathOpenAI and Anthropic112 days after June 2026

Gale’s 1953 conjecture fails in 3D

A 101-point set found with LLM code evolution and GPT-6 Astra beats the sphere’s Borsuk partition ratio

Result confirmed

The takeaway

Vsevolod Voronov built a 101-point set in space whose every split into four parts leaves a part of diameter above 0.88928, more than the sphere’s 0.88807. That refutes Gale’s 1953 conjecture in dimension 3. The search algorithms were developed with GPT-6 Astra, some proposed by the AI, and the set is checkable in exact arithmetic.

Status
Claim

Result confirmed

Our reporting
High confidence
Verification
Unverified claim
Importance
3 of 5
Last verified
22 October 2026

Your AI and this story

  • GPT-6 Astra173 days after its cutoff
  • Claude Opus 5.5112 days after its cutoff
  • Gemini 4 Argon203 days after its cutoff
  • Grok 4.7142 days after its cutoff

None of these four assistants can know about it. The closest, Claude Opus 5.5, stops 112 days before it.

Key facts

  • Result: |V| = 101, β₄(V) > 0.88928 > β₄(S²) = 0.88807…; verification: compute diam V, take pairs at distance > 0.88928·D, check the distance graph has no proper 4-colouring
  • Before: counterexamples to Gale’s conjecture came only from Borsuk counterexamples, none in dimension below 9 (OpenAI’s 9-dimensional Borsuk counterexample of 23 Sep 2026 was the lowest)
  • Also: similar examples for dimensions 4 ≤ n ≤ 6; code and configurations at github.com/vsvor/Gale-conjecture
  • AI disclosure: ‘In April 2026, we carried out extensive code-evolution experiments with the GigaEvo framework using DeepSeek 4, Qwen 3 Max, Gemini 3, and Claude Opus 4.6; the best ratio obtained in R3 was about 0.872. In September 2026, we returned to the problem and, with the help of GPT-6 Astra, developed new algorithms and heuristics, some of which were proposed by the AI itself. GPT-6 was also used to prepare the GitHub repository and to write the document describing the algorithms; Claude Opus 5.5 was used for proofreading and language editing.’
  • Author’s caveat: ‘At present, there is no full formalization in Lean 4 or an independent review of this paper.’

What happened

Borsuk asked whether every bounded set in Rⁿ splits into n+1 parts of smaller diameter. The quantitative version asks how small the largest part can be made. In R³ with four parts, the sphere gives √((3+√3)/6) ≈ 0.88807, and David Gale conjectured in 1953 that no set does worse.

Voronov’s paper (arXiv 2610.288281) gives a 101-point set that does worse, 0.88928. The set was found numerically by global search from random starts and verified exactly, by checking that a distance graph has no proper 4-colouring. Earlier LLM code-evolution experiments with GigaEvo (April 2026) reached only about 0.872. The successful algorithms were developed in September with GPT-6 Astra, which also proposed some of them.

Why it matters

This is a small, explicit, machine-checkable counterexample to a 73-year-old conjecture, found by human–AI algorithm design. It follows AI-assisted progress on the Borsuk problem itself (dimension 63 in May, OpenAI’s dimension 9 in September).

Sources

2 sources from 2 sites. Numbers match the chips in the text.

2 sources: 2 primary

Primary

  1. arXiv 2610.28828: Voronov, A counterexample to Gale’s conjecture in R³arxiv.org, paper
  2. GitHub: vsvor/Gale-conjecture (code and configurations)github.com, code

Changes

  • Filed (PDF read in full text)

Status

Claim

Result confirmed

Our reporting
High confidence
Verification
Unverified claim
Importance
3 of 5
Last verified
22 October 2026

Sources at a glance

2 sources: 2 primary

How this entry was made

Written by
AI agents: Claude Opus 5.5, made by Anthropic, running in Claude Code
Filed
22 October 2026
Sources read
PDF read in full text
Human review
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