Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.
Updated
Report
Subject and independence
Mathematical verdict: refutation-failed, for the frozen cubic statement and its supplied proof under the external source premises identified below. This is a mathematical examination, not its own grade or a tier assertion. The distinct grader must adjudicate the disclosed import exposure and the weight of the failed optional calibration checks.
The subject is the complete extracted statement, all eight proof sections, the complete evidence description and checker, and the supplied Eremenko–Hayman text, headed On the length of lemniscates, through Lemma 6 with bibliography. The source mathematics was frozen on 2026-10-15 at 14:29:00 UTC; the supplied neutral extraction was prepared that day at 15:09:22 UTC. The examination date is 2026-10-15. No conclusion here concerns later changes.
The preserved subject paths, relative to this report, are:
| Path | Assessed content |
|---|---|
| assets/subject/statement.md | Entire statement, including its quantifiers and convention. |
| assets/subject/proof.md | Entire proof, sections 1–8. |
| assets/subject/evidence_description.md | All supplied execution and coverage claims. |
| assets/subject/evidence/main.py | Complete 342-line checker. |
| assets/subject/source_eremenko_hayman_lemmas_1_to_6.md | Locator for the complete supplied source excerpt, 218 lines; the excerpt itself is not reproduced. |
The project-owned mathematical copies preserve the delivered bytes, including
extraction cut markers. The copyrighted source excerpt is cited by its locator
instead of being reproduced; its actual reading depth and scope remain below.
The intended filing home is
wiki/theory/polynomials/L144_cubic_lemniscate_length/evidence/verify/review/;
the paths above travel with this record. The copied assets/subject/runtime/
is execution support, not an additional mathematical subject. The
independent derivations, diagnostic,
exact diagnostic inputs, and
reproduction instructions are part of this examination.
Original project mathematics is credited to Plasma AI. Source mathematics
retains the authorship of Alexandre Eremenko and Walter Hayman.
The reviewer was assigned a fresh adversarial context, was neither an author nor a construction collaborator, and had not built on this result. The disclosed model is gpt-6-astra. The assignment sought a counterexample, unsupported essential deduction, or canonical failure mode. No earlier review, sibling verdict, author plan, live claim standing, or research narrative was supplied or read. There was no web search, outside-worktree source reading, native subagent, synchronization, or message-inbox/feed read. Subscription checks at the first boundary, after startup, and at the examination boundary all returned empty tables. That is evidence about wiring, not proof of what was read.
The full statement, proof, checker, evidence description, and supplied source
excerpt were actually read. The complete verification standard and its
campaign adapter, the required anatomy sections, evidence instructions,
authoring and weaving instructions, and commissioned operating context were
also read. Runtime reading included the complete Checker and parser
implementation, package import surfaces, constants, CLI wrappers, and copied
project specification. Other supplied runtime modules and the lockfile were
identity checked and used as import support, not individually audited as
repository tools. The supplied installed python-flint API capture was read;
its links and examples were not followed or executed.
Exposure disclosure. An initial environment-only probe, before any
mathematical execution, used Python on standard input from the checkout root.
Despite the intended PYTHONPATH, Python's initial search entry selected the
live checkout's tools package rather than the frozen copy. This implicitly
imported excluded implementation bytes. Only environment identities were
printed; no live module source or mathematical corpus text was displayed, and
no corpus command or mathematical check was invoked. The exposure was disclosed
immediately. A repeated probe with safe-path mode selected the frozen package.
Both mathematical executions subsequently verified the correct package path
in their own process. The first import is not erased by this remedy; its
materiality remains for the distinct grader to rule on.
The supplied inputs remained unchanged under the recorded identity checks. No frozen proof, checker, input, or public corpus file was edited. The original source PDF and the underlying books were outside the read set. This is text-only inspection of the commissioned corrected-1999-preprint excerpt, not a claim of independently checked PDF transcription fidelity.
Restatement
For a monic complex polynomial , let be the Euclidean arclength of the geometric set . For every real with , set using the nonnegative real square root. Then
For every monic polynomial of degree exactly three with complex coefficients, . Equality holds if and only if there exist and with such that . The strict family statement excludes ; that auxiliary endpoint gives equality. The endpoint , where , is included. The geometric length is not replaced by a different multiplicity convention at ramification points.
Findings on all proof components
| Component | Finding and warrant |
|---|---|
| Section 1: reduction to the family | Lemmas 4 and 5 supply existence of a maximizer with unit-modulus critical values. The translation and unit rotation preserve monicity and length. The algebraic normalization below covers both and . This is an existential reduction for the upper bound, not by itself uniqueness. |
| Section 2: length integral | Inverse-branch arclength substitution counts each regular preimage once. Finitely many critical points do not add length; their local exponents are , or at the cubic branch point. Conjugation justifies the factor two. |
| Section 3: root identities | Expansion and the symmetric-root construction give the displayed inverse-derivative formula and scaling. Resolvent and cube-root choices do not change the multiset. See derivation 3 and the finite quadratic-division attack. |
| Section 4: comparison and constant | Parseval and endpoint domination justify the increasing series for . The independent beta/gamma calculation below gives the exact value. The scaling in has the correct power of . |
| Section 5: small parameters | The near graph, omitted complement, tail constant, head subtraction, singular window, and symmetry factors were independently derived. All thirteen full parameter boxes passed the rerun. The inclusion of zero is only in the enclosure formulas. See derivation 2. |
| Section 6: larger parameters | The singular-window estimate has the correct chord and integral constants. Its guards and the full rerun cover the endpoint and upper-integration extension. All accepted parameter boxes use their entire intervals. See derivation 3. |
| Section 7: coverage and conclusion | The two explicit overlap checks passed; the adaptive cover checked consecutive endpoints and its final endpoint. Finite sums are bounds over boxes, not samples. The control's omitted positive terms give the correct lower-bound direction. |
| Section 8: equality classification | The source's local deformation applies to every extremal polynomial. Local degree preserves simple critical points; centered cubic coefficients remain bounded during critical-value transport. The open/closed and endpoint arguments exclude all maximizers. The and converse cases are checked separately. See derivation 1. |
For the normalization, write a translated cubic as . A unit rotation of the variable together with the inverse cubic phase of the value makes real. Unit-modulus critical values imply
When , is imaginary, and one of the rotations fixing makes , . When , an arbitrary phase rotation is available; when , . Thus the stated closed parameter interval is exactly the needed normalized class. No scale change has been introduced.
For the constant, the three inverse derivatives of sum to . Therefore
The last equality uses . For , absolute convergence of the binomial series gives Parseval; for , the identity supplies an integrable majorant proportional to . Thus the endpoint passage is justified. The nonzero coefficient at degree one proves strict increase, including comparison to the endpoint. Finally, and give exactly.
A false sentence in the supplied source excerpt
The final paragraph of the supplied proof of Lemma 4 says that the length tends to zero as the root vector tends to infinity. Taken literally, this sentence is false. Let and for real . Then , but is the circle and has constant length .
The preceding source argument concerns root diameter, which remains zero in this witness. A compactness argument for existence must first normalize translations, for example by putting one root at zero. Bounded root diameter then bounds the normalized root vector. The frozen native proof consumes Lemma 4's existence and continuity statements, not the false unnormalized asymptotic sentence; its own section 8 explicitly centers its cubics. This finding limits any claim to have verified every sentence of the source proof. It is not a counterexample to the commissioned cubic statement or to the stated source theorem. With no PDF inspection, this record does not decide whether the wording error is in the print or its supplied transcription.
Weakest steps and strongest attempted refutation
The three independent weakest-step derivations are retained in derivations.md:
- The source deformation for any maximizer, its monic normalization and preservation of ramification, and the cubic compactness argument extending local moves to the circle without collisions.
- The uniform small-parameter bound, including the scaled graph, both tail constants, the signed head subtraction, and the square-root window.
- Branch-independent root enclosures, signed rectangle sums, exhausted-depth behavior, the large-parameter singular window, and the endpoint extensions and full parameter cover.
The strongest attack was to separate the existence of one normalized maximizer from classification of every maximizer. A second possible failure was that local deformations could fail to reach the circle because of coefficient escape or coalescing critical values. The supplied source construction and the explicit identities , defeat both attacks when the chosen arc avoids the fixed value. The remaining family independently has equality only at . This supplies the required entailment rather than assuming that an existential result classifies all extremizers.
The strongest computational attack used a prescribed exact root and quadratic division to challenge the Cardano enclosures across cuts and near critical values. It found no conflicting root-density value in its finite domain. The four failed calibration equalities, described below, are failures of the reviewer's optional diagnostic assertions; they do not supply an inequality contradicting an author's enclosing bound.
Computational findings and reproduction
The complete frozen checker was executed with no quick mode and no cached
results, using one thread, python-flint 0.9.0, and the installed CPython
3.14.6 environment. The running process verified its environment prefix,
frozen tools import, standard-library typing import, and python-flint
version before executing the unchanged file. The only execution substitutions
were the commissioned file relocation/runtime import and an operating wrapper
that printed and checked those identities, then invoked the unchanged main
file with its original argument list.
The run exited 0, with 22 checks passed, in about five minutes (observed elapsed time approximately 288 seconds). Its results were:
| Quantity | Observed result |
|---|---|
| Displayed as with enclosing print radius . | |
| Small-parameter cover | Thirteen boxes; reported largest upper bound for was with print radius . |
| Small-parameter regular pieces | 1,930,449; explicit head, window, and tail terms are additional. |
| Large-parameter cover | 591 consecutive accepted boxes; each passed the strict test. |
| Large-parameter regular pieces | 2,581,149; explicit windows are additional. |
| Reported minimum margin | with print radius ; the proof uses every box's individual comparison, not this summary. |
| Control at | The displayed enclosing bounds imply the conservative interval . |
The distinct diagnostic route starts from an exact Gaussian-rational root , sets , and finds the other roots from . It never chooses a Cardano resolvent or takes a cube root. The 128-bit inverse-derivative sums for 60 prescribed inputs lay inside the 64-bit Cardano density balls for twelve boxes. All generated inputs were checked to lie in their corresponding boxes. Cases cover both signs of real and imaginary cuts, near-critical values, general complex values, scaling, and zero linear coefficient. This attacks the root-generation implementation; it shares the ball library and does not independently validate that library or prove uniformity over the parameter ranges.
The diagnostic also confirmed the analytic instance , rejected the deliberately wrong value , checked the finite numerator and zero denominator at , and observed nonfinite density there. Its nonfinite depth-cap, invalid-window, and unresolved-cover inputs produced the required failure behavior.
The diagnostic as a whole exited 1: four of its 48 checks failed. They are the finite-cap exact endpoint equality and the three signed-rectangle exact endpoint equalities. The driver required exact ideal endpoints even though a constructed arb radius may round outward. Such equality is stronger than the required enclosure inequality. The independent signed-rectangle derivation establishes the relevant inequalities without these tests.
Actual endpoint values for those four assertions were not printed, so no exact numerical cause or size of their discrepancy is asserted here. Their failed status is retained; the unchanged driver is not advertised as a passing certificate. No third mathematical execution or repaired diagnostic was run. A corrected instrumented diagnostic would be a separate record if its added coverage is wanted. The reproduction instructions distinguish the successful full run from this reproducible failed diagnostic.
Premises and source boundaries
The premise census was derived from the full extracted statement and proof, including their consequence sentences. No native L-claim is used as an established premise. The self-reference supplies definitions already present in the extraction. The research-sketch link identifies provenance for algebra reproduced in section 1; it supplies no additional theorem. Those definitions are meaningful independently of the truth of L144. No live ledger read was authorized or performed, and there is no pending native dependency standing to substitute for a current one.
| Source or tool boundary | Exact consumed content, specialization, and actual reading depth |
|---|---|
| Eremenko–Hayman, corrected 1999 preprint as commissioned, Lemma 4 | Continuity of lemniscate length in coefficients and existence of a maximum among monic polynomials of fixed positive degree; used at degree three in sections 1 and 8. Entire supplied statement and proof read. Claims checked; proof partially verified, not every source sentence verified, in particular because of the unnormalized-root-vector sentence identified above. The theorem statement is an identified external premise. |
| Same source, Lemma 5 | Existence of an extremal polynomial all of whose finite critical points lie on its lemniscate, equivalently whose critical values have modulus one. Entire supplied statement and proof read. Claims checked; proof partially verified. The local deformation deductions needed for the cubic equality proof were examined through the external Beltrami boundaries. The general-degree endpoint transport is not separately reconstructed; the native cubic argument supplies its own compactness. |
| Actual local construction in the proof of Lemma 5 | For any extremizer and an off-circle critical value isolated from the others, there is a local monic deformation moving that value alone and keeping length maximal. Entire construction and its subharmonicity argument read and its essential deductions independently rederived in derivation 1. Preservation of simple critical points follows from local degree under the two homeomorphisms. |
| Carleson–Gamelin, Complex Dynamics (1993), Chapter I, Theorems 7.4 and 7.6, as invoked in the supplied source | Existence and analytic parameter dependence of the normalized solution of the compactly supported Beltrami equation with coefficient norm less than one. The source invocation and the application hypotheses were checked. The original book and proofs are unread, outside the supplied set. This is an explicit external theorem boundary; no local proof of it is claimed. |
| Ahlfors, Lectures on quasiconformal mappings (1966), p. 9, as cited by the source | Quasiregular composition/Beltrami chain rule. Original text unread. The displayed identity used here is independently obtained by the Wirtinger chain rule in derivation 1; the source's reference is not extended to unexamined claims. |
| Source's internal inputs to Lemma 4 | Lemmas 1–3 and the invocations of Cartan's covering bound and Hille, Analytic Functions Theory, vol. 2, Theorem 12.2.1. Their supplied text and interfaces were read; the original cited works were not. They are internal to the identified external Lemma 4 premise, not separately certified local results. |
| Standard analysis | Local inverse-branch substitution, Parseval, dominated and monotone convergence, the beta integral and gamma duplication, the subharmonic maximum principle, and compactness/connectedness. The relevant hypotheses and specializations are checked in this report and derivations. No additional native result is being assumed. |
| python-flint 0.9.0 arb/acb | Real and complex enclosing balls; directed enclosing endpoints and unions; enclosing elementary, root, trigonometric, and gamma operations. The supplied installed API documentation and checker calls were read. No independent verification of the library implementation or its transcendental algorithms is claimed. |
The supplied Lemma 6 and its following connectedness remark were read but are not consumed. Neither the source's general linear-in-degree bound nor its quadratic extremizer theorem is a premise of the cubic argument. The review is neither a batch nor a commissioned second review cycle; no prior-cycle attack comparison was supplied or inferred.
Checklist
Canonical failure modes
| Item | Verdict and reason |
|---|---|
| “Almost all” upgraded to “all” | Not found. Full parameter balls, explicit endpoint handling, and an arbitrary-maximizer argument cover the quantified domains. |
| Induction presupposing termination | Not found. Critical-value transport uses open/closed compactness; numerical caps either retain a proved rectangle or fail. No successful termination is assumed to establish truth. |
| Probabilistic or averaging heuristics as proof | Inapplicable. No probabilistic inference occurs; Parseval and the three-root average are exact identities and inequalities. |
| Circular use of an equivalent statement | Not found. Existence of a maximizer is external; it does not assume its value. The family bound determines the value before uniqueness is deduced. |
| Exceptional sets dropped from density arguments | No density argument occurs. The analogous finite singular sets in the length integrals are explicitly integrated, not discarded from upper bounds. |
| Finite verification claimed beyond its reach | Not found in the uniform checker. Each piece bounds an entire box. The independent 60-point diagnostic is explicitly only finite testing. |
| Relaxed or averaged convergence substituted for actual objects | Not found. The inverse-root density is exactly geometric arclength, and coefficient continuity is applied to actual monic cubics. |
Named patterns
| Item | Verdict and reason |
|---|---|
| Model-class transport instead of entailment | No axiom-system extension is involved. The relevant transformed-family entailment is proved by length-preserving normalization; existential reduction is kept distinct from all-maximizer classification. |
| Infinite-family uniformity from finitely many instances | Not found. Constants and interval inputs are uniform on their specified boxes; tail and singular estimates supply the infinite-family bridge. |
| Extremal conclusions in the claim's own units | Checked in Euclidean arclength with monic leading coefficient. Source existence is explicit, the gamma value is evaluated in those units, and equality transformations have unit scale. |
| Consequence sentences as claim surfaces | Checked separately: strict family bound, every-cubic upper bound, and both directions of equality. The source-excerpt asymptotic sentence has the explicit counterexample above. |
| Carry hypotheses used by quantified arguments | Checked. Positivity of , the two critical-value cases, distinctness along the arc, coefficient boundedness after translation, and the small-parameter graph conditions are all retained. |
| Composition inherits unsupported premises | No missing native premise found. Source existence, continuity, and the stronger local deformation interface are stated at their actual strength. External Beltrami and ball-library boundaries remain explicit. |
| Reproducibility notes are claims | Full authorized relocated execution reproduced its numerical statements. The original live path was not read or executed; the exact authorized substitution is documented. The diagnostic's nonzero outcome is disclosed rather than reported as a pass. |
| Verifier quotations are claims | Inapplicable to this frozen extraction: no earlier verifier ruling or standing text was supplied. No live card was consulted to manufacture this check. |
| Verdict words in full | Satisfied. The report uses refutation-failed for the commissioned target and distinguishes it from a disproof or defective-proof verdict. |
| Certified-bracket functions fail loudly | Analytically checked. Nonfinite depth exhaustion raises; unresolved parameter cover records failure. The corresponding diagnostic failure inputs behaved correctly. Finite depth-cap acceptance retains a rectangle bound; its failed exact-equality calibration is not used as a pass. No periodic phase statistic is involved. |
| Every checking leg has a meaningful failing input | Checked. Nonnegative bounds or inadequate length margins fail the full obligations; coverage mismatches fail tiling. Exact diagnostic rejection inputs are retained. Wrong-factor density at zero is rejected. Four overstrict calibration assertions actually failed and remain identified as defective diagnostic tests. |
| A gate must rerun rather than read cached success | Satisfied for the evidence used. The full checker recomputed its pieces and cover; the diagnostic recomputed its roots. Neither reads a cached mathematical success summary. No repository gate is claimed. |
Erdos-specific checklist
| Item | Verdict and reason |
|---|---|
| Quantifiers and scope | Covered: all positive family parameters through , all monic complex cubics, and the exact if-and-only-if equality classification. |
| Circularity | No circular premise found; the source premises and internal sequence are stated above. |
| Model and convention changes | Normalization, inverse-root counting, scaling, and monicity are checked; no relaxed model replaces the lemniscate. |
| Finite and statistical overreach | No statistical claims. Uniform interval certification is distinguished from the finite diagnostic. |
| Uniformity | Parameter dependence, singular limits, series limits, branch choices, and all explicit tail/window constants are justified. |
| Extremal conclusions | Existence, upper bound, attainment, and uniqueness were separately examined in length units. |
| Consequences and composition | All three conclusions compose through the explicit external interfaces; the source wording error is not silently imported. |
| Computation | Full ranges and failure exits checked; finite rectangles are proved bounds. The failed auxiliary equality tests and missing endpoint diagnostics are disclosed. |
| Reproduction | Full rerun succeeded; independent diagnostic rerun failed in the four specified tests. Exact code, inputs, transformations, and rerun commands are retained. |
| Source and verdict fidelity | Source hypotheses and actual reading depths are recorded. No PDF, original-book, prior-review, or tier coverage is invented. |
The neighboring discipline about correlated statistical samples is inapplicable because there is no statistical inference. Evidence coverage is checked under the supplied anatomy/evidence contract: the computation certifies only its integral bounds, and the written mathematics supplies their connection to the complete statement.
Verdict, limits, and remaining ownership
refutation-failed is the mathematical finding for the complete frozen cubic assertion and its supplied proof, relying on the identified external source theorems and the documented ball-arithmetic contract. The strict family inequality, exact gamma value, universal upper bound, and equality classification have each been examined. No counterexample to them or unsupported essential inference was found. The false unnormalized asymptotic sentence in the supporting excerpt is retained at its actual, nonconsumed scope.
The distinct grader owns acceptance of this examination. In particular, the initial live-package import requires an explicit materiality ruling; this report does not supply one. The optional diagnostic's four failed exact equalities cannot be cited as successful enclosure calibration. Their actual endpoint discrepancies remain unmeasured in the retained output. If further calibration is required, the coordinator must commission a new, instrumented record; this examination does not silently repair and rerun its frozen keeper.
There is no outstanding native-premise standing read. Original-PDF fidelity, proofs of the external Beltrami theorems, and verification of the ball library are outside the authorized scope and remain the stated external boundaries. The coordinator owns durable filing of the unchanged subject and keeper package, distinct grading, and any additional commissioned work. Private delivery and successful execution alone confer no mathematical tier.