Plectis Atlas
Search

↑ and ↓ move, Enter opens, Esc closes.

Show on the map

Counterexamples to stable-Morse and strong Arnold fixed-point bounds

OpenAI groups related papers into a “family”. OpenAI’s catalogue describes this one:

Disproves stable-Morse lower bounds for nondegenerate Hamiltonian fixed points: on simply connected closed Kähler manifolds of real dimension 22, the deficit below the stable Morse number is unbounded. A separate Hamiltonian diffeomorphism of the complex quadric threefold has exactly three fixed points, fewer than the four critical points required of every smooth function. (OpenAI’s Lean note)

Lean is a language for mathematical statements and proofs that a computer can verify. The assessments below ask whether those statements express the result OpenAI describes here.

The independent assessments find that the Lean statements express only part of the result described above, or a narrower statement. Read the assessments

The paper states

Theorem 1.1

In Hamiltonian Fixed Points Below the Stable Morse Number in Dimension Twenty-Two, 5 October 2026

Possible match to OpenAI’s description, selected from the papers’ main statements because it shares the most wording. No review confirming the selection is recorded.

Five other possible matches are listed below the card, among them Theorem 1.1 in Sharpness of the Cyclic Integral Floer Bound Below the Stable Morse Number and Theorem 1.1 in A nondegenerate counterexample to the Morse-number Arnold bound.

For every integer m\geq1, there exist a simply connected closed Kähler manifold (M_m,\omega_m) of real dimension 22 and a smooth one-periodic Hamiltonian H_m such that all fixed points of \phi_{H_m}^1 are nondegenerate and

\begin{aligned}\SM(M_m)&=80+1968m,\\ \#\Fix(\phi_{H_m}^1) &=\#\Fix_0(\phi_{H_m}^1;H_m)=80+1952m.\end{aligned}

Consequently, with \delta=1/128, for every R>0 some member of this family satisfies

\SM(M_m)\geq R,\qquad \#\Fix(\phi_{H_m}^1)\leq(1-\delta)\SM(M_m).

No Lean statement in the release is paired with this theorem.

Five more possible matches

  • Theorem 1.1 in Sharpness of the Cyclic Integral Floer Bound Below the Stable Morse Number, 5 October 2026.
  • Theorem 1.1 in A nondegenerate counterexample to the Morse-number Arnold bound, 23 September 2026.
  • Theorem 1.2 in Hamiltonian Fixed Points Below the Stable Morse Number, 5 October 2026.
  • Theorem 1.1 in Three fixed points on the symplectic quadric threefold, 23 September 2026.
  • Corollary 1.2 in A nondegenerate counterexample to the Morse-number Arnold bound, 23 September 2026.
Reported proof verification
One Lean statement in the release; three independent groups report that Comparator accepted runs for this file at the version shown here.

Papers

Each paper opens as a reading page in the browser, with the PDF beside it. The statements each paper opens with are on its reading page.

Hamiltonian Fixed Points Below the Stable Morse Number in Dimension Twenty-Two

5 October 2026, current edition.

Read it herePDF

We disprove the stable Morse lower bound for nondegenerate Hamiltonian fixed points with examples in fixed real dimension twenty-two. For every integer m ≥ 1, we construct a simply connected closed Kähler manifold with stable Morse number \(80+1968m\) and a Hamiltonian diffeomorphism with exactly \(80+1952m\) fixed points, all nondegenerate and with contractible orbit loops. The deficit is therefore unbounded, and the fixed-point count is at most 127/128 of the stable Morse number.

Sharpness of the Cyclic Integral Floer Bound Below the Stable Morse Number

5 October 2026, current edition.

Read it herePDF

We construct a simply connected closed Kähler manifold of real dimension 3332 and minimal Chern number one whose Hamiltonian fixed-point count attains the cyclic integral Floer bound while falling below the stable Morse number. The Hamiltonian diffeomorphism has exactly \(1\,872\,232\) fixed points, all nondegenerate and with contractible orbit loops, whereas the stable Morse number is \(1\,872\,264\). Thus the stronger stable Morse bound fails by exactly 32, even when the cyclic integral bound is sharp.

Hamiltonian Fixed Points Below the Stable Morse Number

5 October 2026, current edition.

Read it herePDF

We disprove the stable Morse lower bound for nondegenerate Hamiltonian fixed points by constructing a simply connected closed Kähler manifold with sixteen fewer fixed points than its stable Morse number. All the corresponding periodic orbits are contractible. The construction combines a Hamiltonian involution with integral homology torsion at two different primes; its proof uses finite-dimensional Morse theory and complex blowups.

A nondegenerate counterexample to the Morse-number Arnold bound

23 September 2026, current edition.

Read it herePDF

We construct a smooth one-periodic Hamiltonian on a closed symplectic twelve-manifold whose time-one map has fewer fixed points than the manifold’s ordinary Morse number. Every fixed point is nondegenerate and has a contractible Hamiltonian trajectory. This disproves the Morse-number form of the Arnold conjecture. The deficit can be arbitrarily large among twelve-dimensional examples.

Three fixed points on the symplectic quadric threefold

23 September 2026, current edition.

Read it herePDF

We construct a smooth Hamiltonian diffeomorphism of the complex quadric threefold with exactly three fixed points, at least one of which is degenerate. The critical number and the unit-inclusive rational cup length of this manifold are both four. Thus the example disproves the unrestricted critical-number and rational cup-length forms of the Arnold conjecture.

One Lean statement in this family

Lean is a language for mathematical statements and proofs that a computer can verify. The Lean statement below is shown beside its possible paper counterpart, with the reason they were linked.

For a configured theorem, the Comparator program tests whether OpenAI’s separate proof proves the exact Lean statement using only the allowed axioms. Some statement files instead configure definitions for comparison by name and type. Acceptance does not establish that a formal statement means the same thing as the paper’s theorem.

ArnoldCounterexample

The paper states

The words they share: degenerate, diffeomorphism, equation, fixed, hamiltonian, least, manifold, point, smooth.

Possible Lean counterpart

Selected from shared wording. No review of whether the statements mean the same thing is recorded.

Three-fixed-point Arnold counterexample

ArnoldCounterexample.lean, the release lists it as a main result.

theorem main :    ∃ φ : Q3 ≃ Q3, IsHamiltonian φ ∧ (fixedSet φ).encard = 3 ∧      (3 : ℕ∞) < 4 ∧ 4 ≤ criticalNumber ∧ HasDegenerateFixedPoint φ := by  sorry

This file states the theorem with sorry, a placeholder, in place of its proof. OpenAI supplies a separate proof file. Comparator tests whether that proof proves the statement here.

three independent groups report that Comparator accepted runs for this Lean statement file: cert-machine; MathVet; Neal McBurnett, openai-math-lean-tooling. Who ran the proof-verification program

  • cert-machine records it as “CERTIFIED”.
  • MathVet records it as “comparator-sandboxed-pass”.
  • Neal McBurnett, openai-math-lean-tooling records it as “accepted”.

Read the complete Lean statement

Other mathematical statements in OpenAI’s Lean library

Atlas found these propositions by scanning the text of the project’s Model.lean file. Each name links to its definition, with any associated statement file beside it. This list does not record running Lean to interpret or verify those definitions.

Independent comparisons and proof-verification reports

Does the Lean express the advertised result?

Neither group finds that the Lean statements express or imply the whole advertised result. They describe what the statements express in different terms.

MathVet and Carlos Toledo’s cert-machine independently assessed whether this family’s Lean statements express the whole result OpenAI describes in its catalogue. These are assessments of the family as a whole, not of each paper theorem separately.

MathVet finds that the Lean statements express part of the advertised result (their term: “partial”).

Their note: main gives only the second claim: a Hamiltonian diffeomorphism φ of the quadric Q³ ⊂ ℂP⁴ with exactly 3 fixed points (one provably degenerate) while every smooth function has ≥ 4 critical points (4 ≤ criticalNumber). The headline nondegenerate stable-Morse counterexample on 22-dimensional Kähler manifolds with unbounded deficit has no statement (docs: ‘the separate nondegenerate Morse-number construction is not included’).

Definitions the group asks readers to compare with the paper: Q³ is a hand-built subtype of Projectivization ℂ (Fin 5 → ℂ), not a Mathlib manifold; smooth functions are those with local C^∞ lifts to the unit isotropic cone (IsSmoothFunction), criticality via horizontal lifts, criticalNumber := ⨅ h, (criticalSet h).encard, and Hamiltonian-ness via an explicit lifted isotopy HamiltonianPath with omega v w := 2·Im Σ conj(v_j) w_j tested only on horizontal vectors; all must be trusted to match the standard symplectic notions

“partial”, in their words: Only a special case is stated, or a co-equal headline claim has no challenge statement.

Their method: An independent, model-assisted, pre-referee reading of each family’s challenge statements against its headline claim under a published rubric (PROTOCOL.md), with its own Comparator runs per challenge.

cert-machine finds that the Lean statements express a narrower statement than the advertised result (their term: “NARROWER — DECLARED”).

The gap they name: The stable-Morse clause (unbounded deficit for nondegenerate Hamiltonian fixed points on simply connected closed Kähler 22-manifolds) is not stated.

“NARROWER — DECLARED”, in their words: The challenge statements state less than the headline, and OpenAI’s Lean note says so.

Their method: Every Comparator challenge re-run on Linux with nanoda switched on, decided by a preregistered rule.

OpenAI’s own note on what its Lean covers

The critical-number form of Arnold’s fixed-point conjecture predicts at least as many fixed points as the minimum number of critical points of a smooth function. The formalized counterexample is a Hamiltonian diffeomorphism of the complex quadric threefold with exactly three fixed points, while every smooth function on that manifold has at least four critical points. At least one fixed point is degenerate. The separate nondegenerate Morse-number construction is not included.

AI-drafted comparisons, with no recorded human review

  • Three-fixed-point Arnold counterexample ArnoldCounterexample

    Unreviewed AI draft: states a paper’s theorem as the paper does. States the main theorem: a Hamiltonian diffeomorphism of the complex quadric threefold with exactly three fixed points, fewer than the four critical points every smooth function has. The nondegenerate construction of a companion paper is not included.

Who ran the proof-verification program?

These groups report running Comparator with the release’s Lean statement files. For a configured theorem, it verifies OpenAI’s separate proof against the exact statement; some files instead configure definitions for comparison by name and type. Each row is the named group’s report. Atlas has not repeated the runs.

These reports do not list the software versions, proof-verification programs, axioms, time or memory in separate fields. Any such details in a report’s prose are reproduced below.

Three-fixed-point Arnold counterexample ArnoldCounterexample

Three reports, all at the release’s recorded version.

Reported byTheir wordTheir accountDateOriginal report
cert-machine“CERTIFIED”Re-run through Comparator with the independent nanoda kernel switched on: Lean’s kernel and nanoda both accept OpenAI’s solution.10 October 2026Original report
MathVet“comparator-sandboxed-pass”Re-run through Comparator in a sandboxed virtual machine: accepted.8 October 2026Original report
Neal McBurnett, openai-math-lean-tooling“accepted”Re-run through Comparator with Lean’s kernel: accepted (the check took 751 s; peak memory 10.0 GiB).11 October 2026Original report

Other proofs and exact calculations

These reports examine claims in the papers using exact calculations for finite claims, independently of the release’s Lean proofs. Read each report for the exact claim it covers.

  • Three fixed points on the symplectic quadric threefold, 23 September 2026

    Reported by
    cert-machine
    Method
    Exact computation
    Their verdict
    “CERTIFIED” Exact code written independently from the paper confirms that the published object has the claimed property.
    What it covers
    “a finite component: f(x,y) = e.x + (x-p).y on S^2 x S^2 has exactly three critical points, q_0 = (p,-e) degenerate (Hessian rank 2); NOT the passage to Hamiltonian fixed points on Q^3 nor Crit(Q^3) = 4”
    Original report
    Their report

What these papers cite in the release, and what cites them

These links come from the papers’ bibliographies. A citation records that one paper cites another; how each cited result is used has not been examined here.

Within this family

Papers elsewhere in the release that this family’s papers cite

This family’s papers cite no paper elsewhere in the release.

Papers elsewhere in the release that cite this family’s papers

No paper elsewhere in the release cites this family’s papers.

Explain a result, compare statements or propose a correction

Atlas has no contributed explanation for this family yet. You can offer one with a GitHub account. You receive named credit and disclose any AI assistance.

Each button opens a GitHub form with this page and its source version filled in. Opening the form does not reserve the work.

Offer to write an explanationCompare the Lean statement with the paperSuggest a source attributionSuggest a change

What people have said

Commentary on this family by others, dated and credited. It is commentary, not a finding.

  • An unsigned public tier list, the OpenAI Math Tier List, classes it as a counterexample and rates its significance, if it holds up, as “Major math journal”. The page says that nothing on it is verified.

    Author not stated. Source

  • VibeMathed, VibeMathed: math problems solved with AI, 11 October 2026. Source

    Contested: the release states that Ma’s Theorem 1.5 on Arnold fixed-point counts is contradicted by its own Theorem 1.1 (three entries flagged).

  • Robert Joseph George, Do the Lean statements in openai/math match their papers?, 7 October 2026. Source

    The Lean statement proves only the critical-point lower bound, not the paper’s fixed-point count of three against four, though the review says the disproof itself is unaffected.

Questions awaiting review

Each item identifies a statement, definition or report that needs further review. Its link opens a GitHub form with the source version already recorded.

Read the Lean statement against the paper

  • An AI agent drafted an assessment of which part of the paper this Lean statement expresses. No named human review is recorded. Open the form

Identify the theorem the catalogue describes

  • Family 347 The theorem shown was selected from shared wording with OpenAI’s description. Atlas records no review confirming that it is the theorem the description means. Open the form

Address a question raised in an independent assessment

Compare the proposed paper and Lean matches

  • Family 347 Atlas records no review of whether each linked Lean statement and paper theorem mean the same thing. Open the form