OpenAI claims the planar hot spots conjecture (Lean)
Awaiting review
Importance: major (4 of 5)The takeaway
Family 369 of OpenAI’s 6 Oct 2026 release (paper dated 24 Sept) concerns smooth bounded simply connected planar domains. It claims that on every such domain each first nonconstant Neumann eigenfunction has no interior critical point, so its maximum and minimum occur only on the boundary. This is the strict form of the simply connected case of Rauch’s hot spots problem (1974), stated as a conjecture by Krzysztof Burdzy in 2005. It includes smooth convex domains, long a main open case. The Lean statement passed the community comparator runs. Burdzy (8 Oct) and Rodrigo Bañuelos (23 Oct), whose 1999 paper set out the strict and non-strict forms of the problem, each used ChatGPT to extend the result to nonsmooth domains. Both took OpenAI’s theorem as an input they had not checked. No specialist has published a check of the proof as of 29 Oct.
Status
- Claim
Awaiting review
- Our reporting
- Medium confidence
- Verification
- Lean-verified
- Importance
- Major (4 of 5)
- Last verified
- 29 October 2026
Your AI and this story
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None of these four assistants can know about it. The closest, Claude Opus 5.5, stops 98 days before it.
Key facts
- Claim (abstract, verbatim): ‘We prove the strict hot spots conjecture for smooth bounded simply connected planar domains. More precisely, every nonzero eigenfunction for the first positive Neumann eigenvalue has nonvanishing gradient in the interior, so all its global maxima and minima lie on the boundary. This holds even when the eigenvalue is multiple.’
- Context (paper §1): Burdzy and Werner’s 1999 counterexample with two holes and Burdzy’s 2005 one-hole example show that topology matters; ‘The simply connected planar conjecture is stated explicitly in [Bur05, Conjecture 1.2(ii)].’ Earlier positive cases: convex domains with two axes of symmetry (Jerison–Nadirashvili), lip domains (Atar–Burdzy 2004), all triangles (Judge–Mondal), nearly circular convex domains (Miyamoto)
- Method (paper §1): the starting point is ‘Rohleder’s variational principle for tangent vector fields’. Scalar boundary multipliers are constructed ‘through a reciprocal Green-kernel theorem’, using McCullough and Quiggin’s characterization of complete Nevanlinna–Pick kernels and Schoenberg’s squared-distance embedding. An interior critical point ‘would thus produce too many eigenfunction gradients’
- Lean: comparator challenge HotSpots.lean (OAI.StrictHotSpots.main_theorem) covers nonempty bounded open simply connected planar sets with smooth boundary. It defines the first positive Neumann value as the infimum of mean-zero Rayleigh quotients and takes eigenfunctions in weak form; smoothness of the eigenfunction up to the boundary is a hypothesis, which MathVet lists among definitions to check. Accepted in the oai-math-revised comparator run of 25–26 Oct; MathVet verdict ‘full’, with a sandboxed comparator pass
- Follow-ups that use the theorem as an unchecked input: Burdzy (arXiv 2610.12622, 8 Oct; ‘The paper was generated by ChatGPT with prompts from the listed author’) obtains non-strict hot spots on every bounded simply connected planar domain with compact Neumann resolvent and a simple eigenvalue, and writes: ‘We take this assertion as an input and do not assess or reproduce its proof.’ Rodrigo Bañuelos (2610.32920, 23 Oct) proves the same for domains of finite area and adds examples with cusps and unbounded domains; his Section 1 ‘was generated entirely by ChatGPT (6.1 Sol) in response to a few human prompts’. Jizhou Guo (GitHub preprint, 10 Oct) deduces boundary extrema for every convex planar domain, polygons included
- Criticism (Burdzy’s human commentary, 2610.12622): ‘The OpenAI model that generated [3] missed the theorem presented in this note’, and ‘It is highly surprising that [3] did not cite the spectacular paper of de Dios Pont [2], which shows that the hot spots conjecture fails for convex domains in high dimensions’
- Specialists cite it without assessing it. Atar and Burdzy (2610.19908, 14 Oct, a starlike 3D counterexample): ‘More recently, OpenAI [18] presented a proof for smooth simply connected planar domains.’ Deng, Jiang and Yang (2610.18546, 13 Oct, no AI statement) prove that on every bounded convex planar domain the maximum modulus is attained only on the boundary, and write that OpenAI ‘stated a theorem’. Deng, Gui, Jiang, Yang, Yao and Zou (2604.19003v4) note that OpenAI’s ‘setting, however, excludes polygonal domains with corners’
- Reactions: on Proofs and Prompts (8 Oct), in a reaction signed ‘Mitchell Taylor’ (the page lists no affiliations): ‘In particular, I am happy to see that the hot spots conjecture is true for simply connected subsets of the plane’. AIM (Matthew Colbrook’s tracker) marks problem 003, hot spots on smooth convex planar domains, SOLVED, after what it calls an AI statement-level comparison, not an audit of the proof
What happened
Rauch’s hot spots problem asks whether a first nonconstant Neumann eigenfunction, the slowest-decaying mode of heat flow in an insulated domain, takes its extreme values only on the boundary. Burdzy and Werner disproved the general version in 1999 with a planar domain with two holes, and Burdzy later found a counterexample with one hole. The simply connected planar case, stated by Burdzy in 2005, stayed open. Positive results covered only special classes, such as convex domains with two symmetry axes, lip domains and triangles; general convex planar domains were among the best-known open cases.
OpenAI’s release contains a 21-page manuscript dated 24 Sept that claims the strict form of the conjecture for all smooth simply connected planar domains, for every eigenfunction even when the eigenvalue is multiple. Its Lean statement passed the community comparator runs. Specialists reacted quickly. On 8 Oct Burdzy posted a ChatGPT-generated note deriving the non-strict conclusion for nonsmooth simply connected domains from OpenAI’s theorem, and Bañuelos posted a longer ChatGPT-assisted version on 23 Oct. Both state that they did not examine OpenAI’s proof. Burdzy also criticised the manuscript for missing this corollary and for not citing de Dios Pont’s high-dimensional convex counterexample. Other groups cite the theorem in human-written papers, and Atar and Burdzy show the conjecture can fail in three dimensions even for starlike domains.
Why it matters
This is a claim from OpenAI’s release that the leading specialists in the field have started to build on. They treat it as an unverified hypothesis, and they have used ChatGPT to extend it. If it holds, it settles the planar simply connected case of a 50-year-old problem, including smooth convex domains, while the follow-ups and the 3D counterexample mark where the conjecture stops. No published expert has checked the proof, so the result still depends on a Lean statement and an unrefereed manuscript.
What is disputed or not yet verified
| Verification | Lean formalization of the main theorem (comparator accepted); cited by specialists, but no published expert verification yet |
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Sources
14 sources from 4 sites. Numbers match the chips in the text.
14 sources: 10 primary, 4 reactions
Primary
- OpenAI: Strict hot spots and absence of interior critical points on smooth simply connected planar domains (24 Sept 2026, PDF)github.com, paper
- Lean scope note for family 369github.com, code
- Lean comparator challenge: HotSpots.leangithub.com, code
- oai-math-revised: comparator run on all challenges (LEAN_CHECKS.md)github.com, code
- arXiv 2610.12622: Burdzy, Removing boundary smoothness from the hot-spots conclusion (generated by ChatGPT)arxiv.org, paper
- arXiv 2610.32920: Bañuelos, Hot spots: from smooth to nonsmooth simply connected planar domainsarxiv.org, paper
- arXiv 2610.19908: Atar and Burdzy, A starlike 3-dimensional counterexample to the hot spots conjecturearxiv.org, paper
- arXiv 2610.18546: Deng, Jiang and Yang, strict maximum modulus for Neumann eigenfunctions on convex planar domainsarxiv.org, paper
- arXiv 2604.19003v4: Deng, Gui, Jiang, Yang, Yao and Zou, isosceles trapezoids and kites (declaration on OpenAI’s paper)arxiv.org, paper
- Jizhou Guo: First Neumann eigenfunctions of convex planar domains attain their extrema on the boundary (GitHub preprint)github.com, paper
Reactions
- oai-math-revised: community notes on the hot spots manuscriptgithub.com, discussion
- Proofs and Prompts: 100+ reactions to 100+ solutions (8 Oct)proofsandprompts.com, discussion
- AIM problem 003: Hot spots on convex planar domains (status review)github.com, discussion
- MathVet: fidelity table for openai/math (pre-referee)math.vet, discussion
Changes
- Filed (manuscript abstract and introduction, HotSpots comparator statement and log, MathVet data, the PDFs of arXiv 2610.12622, 2610.32920, 2610.19908, 2610.18546 and 2604.19003v4, Guo’s README, the AIM page, and Proofs and Prompts’ reaction collection)