Mazur Theoremformalization programme

Open, kernel-checked mathematics · Lean 4

Mazur’s classification, built on canonical objects.

A public programme for the full fifteen-group classification of rational elliptic-curve torsion. The Lean Pool cardinality challenge remains a release endpoint; the roadmap also makes finiteness, group structure, and every canonical construction explicit.

Checked Lean
1,792,487 lines
Compiled modules
1877
Active lanes
2 lanes · WIP ≤ 3

Programme principleConstruct the real object before scaling proof volume: progress is earned only when a reviewed API is consumed downstream.

Execution revision · 2026-08-15

One theorem spine. Only startable foundation lanes are active.

Retain Mazur's degree-one formal-immersion route while recording checked but uncredited foundation slices: canonical-linear coherent H0/H1 with pointed proper-curve H1 finiteness; the associated fppf sheafification of the all-degree normalized Picard presheaf together with an honest absolute Picard degree kernel and splitting; genuine secant, tangent, and D(B₁₂) product-neighbourhood addition charts with checked overlap and diagonal comparisons; generic finite free-translation quotient geometry over affine noetherian bases; terminal proper-model specialization at five; and represented polynomial-cusp sections. Proper coherent H0 finiteness, linear connecting maps, Riemann-Roch, proper base change, a pullback-compatible relative degree and relative Pic⁰, Picard representability, gluing and infinity coverage for the global Weierstrass law, actual canonical cyclic and Eisenstein quotient instances, torsion injectivity, represented X_0, and compactification remain open.

Canonical theoremFull classification

MazurTorsion.rationalTorsion_hasMazurClassification

The rational torsion subgroup is isomorphic to one of the eleven cyclic groups or four bicyclic groups in Mazur's theorem.

theorem rationalTorsion_hasMazurClassification (E : WeierstrassCurve ℚ) [E.IsElliptic] : HasMazurClassification E
Release endpointImmutable challenge

Challenge.Mazur.torsion_ncard_le

This immutable challenge is a published corollary, not the project definition of Mazur's theorem. The existing finite/infinite split can also discharge it directly from allowed point orders, while the canonical release additionally proves finiteness and group structure.

theorem torsion_ncard_le (E : WeierstrassCurve ℚ) [E.IsElliptic] : (AddCommGroup.torsion (E⁄ℚ).Point : Set (E⁄ℚ).Point).ncard ≤ 16
Checked argument boundaryMazurTorsion.PrimeOrder.rationalPoint_primeOrder_ne_of_formalImmersionAtFive
Proposed witness packageMazurTorsion.PrimeOrder.DegreeOneFormalImmersionWitness
Proposed private Eisenstein constructorModularCurve.EisensteinQuotient.toDegreeOneFormalImmersionWitness

The generic formal-immersion collision theorem is the checked route-neutral argument boundary. The witness package and its private Eisenstein constructor remain proposed. Do not add winding-quotient, modular-symbol, analytic-rank, symmetric-power, or global cyclotomic machinery to the critical path.

01

cohomology-picard-jacobian

Canonical curve cohomology to Jacobians

Current package
Current WP exit criterion

A cover-independent canonical K-linear H⁰/H¹ API, including H⁰/global-sections compatibility and coefficient-morphism and connecting-map linearity, is available to the proper-curve finiteness package.

Lane goal

A represented Jacobian and pointed Abel–Jacobi morphism compile with base-change consumers.

02

represented-modular-curve

Represented X₀(N) vertical slice

Current package
Current WP exit criterion

Starting from the checked over-base additions on D(x₁ - x₂) and D(B₁₂), their equality on the exact intersection, and the diagonal tangent comparison, glue their union; then add the infinity charts and coverage, prove the commutative group laws, and refactor MazurTorsion.XZeroFortyNine.orderFortyNineConcreteGroupSchemeInterface to consume the result without supplied [GrpObj (toOver E)] or CanonicalPointGroupLawCompatibility E shadow inputs.

Lane goal

An exact-order-49 point reaches an honest represented X₀(49) point without a supplied point-equivalence shadow.

The weighted roadmap

A dependency graph with an honest denominator.

The programme totals 1000 points. Stage weights estimate effort across the whole theorem—not file counts, issue counts, or perceived mathematical elegance.

Stage contract

What this stage must define and prove

These are the concrete APIs and results that count as this stage’s scope. Node cards below show how the work is divided and connected.

  • definitionIntegrated
    MazurTorsion.RationalTorsion

    The rational torsion subgroup used by every downstream cardinality and point-order theorem.

  • definitionIntegrated
    MazurTorsion.cyclicOrders and remainingKubertForbiddenOrders

    The exact allowed cyclic orders and the four composite callbacks still exposed by the baseline.

  • theoremIntegrated
    MazurTorsion.rationalTorsion_orders_mem_cyclicOrders_of_remaining_obstructions

    The compiled point-order reduction with only prime orders at least 11 and orders 18, 25, 35, and 49 left open.

  • theoremIntegrated
    MazurTorsion.torsion_ncard_le_of_explicit_arithmetic

    The exact ncard-at-most-16 target once every rational torsion point has an allowed order.

  • theoremIntegrated
    WeierstrassCurve.Affine.approx_parallelogram_law / MazurTorsion.rationalLogHeightNorthcott

    The checked rational height-descent inputs that prove torsion finiteness directly through Mathlib's finite-torsion descent theorem, without Mordell–Weil finite generation.

All 1 dependency nodes

50.0 of 50 points integrated
Done50 pts

Finite-group classification and cardinality assembly; direct rational-torsion finiteness; the generic finite-abelian rank-two presentation; full 2-, 3-, 4-, 5-, and 7-torsion obstructions; exceptional products; and unconditional exclusions of orders 14, 15, 16, 20, 21, 24, and 27.

  • definitionIntegrated
    MazurTorsion.RationalTorsion

    The rational torsion subgroup on which the point-order and cardinality reductions are stated.

    MazurTorsion.GroupTheory.ClassificationCardinality
  • definitionIntegrated
    MazurTorsion.cyclicOrders

    The finite set of cyclic point orders allowed by the target classification.

    MazurTorsion.GroupTheory.ClassificationCardinality
  • definitionIntegrated
    MazurTorsion.remainingKubertForbiddenOrders

    The exact residual composite-order callbacks exposed by the imported baseline.

    MazurTorsion.Arithmetic.PointOrder
  • theoremIntegrated
    MazurTorsion.rationalTorsion_orders_mem_cyclicOrders_of_remaining_obstructions

    The checked point-order reduction from the remaining prime and composite exclusions.

    MazurTorsion.Arithmetic.PointOrder
  • theoremIntegrated
    MazurTorsion.torsion_ncard_le_of_explicit_arithmetic

    The checked cardinality bound once the explicit point-order hypotheses are supplied.

    MazurTorsion.Arithmetic.CardinalityReduction
  • theoremIntegrated
    WeierstrassCurve.Affine.approx_parallelogram_law

    The checked naïve-height estimate consumed by Mathlib's direct finite-torsion descent theorem.

    MazurTorsion.Foundations.NaiveHeightDescent
  • definitionIntegrated
    MazurTorsion.rationalLogHeightNorthcott

    Northcott's property for rational logarithmic height, completing the direct torsion-finiteness input without finite generation.

    MazurTorsion.NumberTheory.RatNorthcott
  • theoremIntegrated
    MazurTorsion.rationalTorsion_finite

    Apply rational Northcott and the approximate parallelogram law to Mathlib's finite-torsion descent theorem, without full Mordell–Weil finite generation.

    MazurTorsion.Arithmetic.RankTwoReduction
  • theoremIntegrated
    MazurTorsion.exists_rankTwoPresentation_of_allowed_orders_and_forbidden

    Put any finite abelian group satisfying the allowed-order hypothesis and exactly c2Cube, c3Square, c5Square, and c7Square into rank-two invariant-factor form; c4Square, c2c10, and c2c12 remain classification-only.

    MazurTorsion.GroupTheory.FiniteClassification
Needs
foundation node
Unlocks

Interactive dependency graph

Every node, edge, and hand-off.

Read left to right across the six programme stages. Select any node to inspect its definitions, theorem contracts, dependencies, and downstream consumers.

Graph focus
Integrated Open Planned or blocked Paused
Mazur theorem dependency graph48 formalization nodes arranged in 6 stage columns. Select a node to inspect its exact scope.Integrated baseline01 · Integrated baseline1 nodes · 50 ptsFinite-level endpoints02 · Finite-level endpoints8 nodes · 100 ptsShared algebraic geometry and isogenies03 · Shared geometry13 nodes · 300 ptsPrime-level infrastructure04 · Prime infrastructure14 nodes · 400 ptsMazur's prime-order argument05 · Prime argument8 nodes · 100 ptsIntegration and hardening06 · Integration4 nodes · 50 ptsImported sorry-free Mazur baselineMT-BASE-INTEGRATED50 pts · DoneThe five-coset bound on X_1(11)MT-X11-COSET12 pts · PausedExpose the order-11 endpoint from the prime theoremMT-X11-JOIN2 pts · BlockedClassify the noncuspidal rational points on X_1(13)MT-X13-NONCUSP26 pts · PausedClassify the noncuspidal rational points on the order-18 curveMT-X18-NONCUSP18 pts · PausedExclude exact rational order 25MT-O25-EXCLUDE16 pts · PausedExclude exact order 35 with the shared formal-immersion engineMT-O35-EXCLUDE14 pts · PausedBridge order 49 directly to the classified X_0(49) curveMT-O49-TOWER10 pts · OpenAssemble the genuinely exceptional finite levelsMT-FINITE-JOIN2 pts · BlockedFinite support of orders of rational functionsMT-TC-A1-ORDER-SUPPORT15 pts · DoneDegree-zero product formula on a proper smooth curveMT-TC-A2-PRODUCT-FORMULA15 pts · DoneDimension of a product of abelian varietiesMT-TC-E0-PRODUCT-DIM2 pts · DoneDivisor-line-bundle dictionaryMT-TC-A3-DIVISOR-LINE-BUNDLE18 pts · Research OpenCoherent cohomology of proper curvesMT-TC-B1-COHERENT-COHOMOLOGY35 pts · BlockedRiemann-Roch and Serre duality for curvesMT-TC-B2-RR-SERRE25 pts · BlockedRelative cohomology and base changeMT-TC-C1-RELATIVE-COHOMOLOGY30 pts · BlockedRelative effective divisors and symmetric powersMT-TC-C2-SYMMETRIC-POWERS15 pts · BlockedNormalized relative Picard functorMT-TC-D1-PICARD-FUNCTOR35 pts · BlockedRepresent Pic⁰ and construct its universal bundleMT-TC-D2-PICARD-REPRESENTABILITY45 pts · BlockedJacobian variety and sanity checksMT-TC-E1-JACOBIAN-VARIETY20 pts · BlockedAbel-Jacobi universal property and base changeMT-TC-F1-ABEL-JACOBI20 pts · BlockedCyclic subgroup quotients and classifying dataMT-EC-ISOGENY-WEIL25 pts · BlockedNeron models for the Eisenstein quotientMT-NERON-BASE40 pts · BlockedIdentity components and toric modular fibresMT-NERON-COMPONENTS30 pts · BlockedTorsion specialization at the Eisenstein quotientMT-NERON-SPECIALIZATION30 pts · BlockedFinite-flat commutative group schemes for Eisenstein rank zeroMT-FFGS-BASIC20 pts · DoneAdmissible filtrations and fppf cohomologyMT-FFGS-CONNECTED-ETALE20 pts · BlockedRaynaud uniqueness and the Eisenstein rank-zero criterionMT-FFGS-OORT-RAYNAUD40 pts · BlockedThe X_0(N) moduli point attached to rational prime torsionMT-X0-MODULI30 pts · BlockedIntegral X_0(N), cusp completions, and auxiliary q-parametersMT-X0-INTEGRAL30 pts · BlockedCusps, Atkin-Lehner transport, and reduction typeMT-X0-CUSPS20 pts · BlockedThe modular Jacobian and cusp-based Abel-Jacobi mapMT-X0-JACOBIAN20 pts · BlockedHecke action and cotangent q-expansionsMT-X0-HECKE30 pts · BlockedOptimal quotients and formal immersion at the cuspMT-X0-EISENSTEIN-ALGEBRA30 pts · BlockedA nontrivial rank-zero Eisenstein quotientMT-X0-EISENSTEIN-QUOTIENT40 pts · BlockedCyclotomic unramified character extensionsMT-CYCLOTOMIC-UNRAMIFIED20 pts · PausedAttach the modular point and its finite quotient imageMT-PRIME-SEMISTABLE10 pts · BlockedDetect cusp reduction at the auxiliary prime fiveMT-PRIME-OUTSIDE-IDENTITY10 pts · BlockedFormal immersion forces potentially good reduction at fiveMT-PRIME-EISENSTEIN-SPECIALIZATION20 pts · BlockedPreserve exact prime-to-five order under good reductionMT-PRIME-DIVISION-FIELD15 pts · DoneExclude additive reduction at fiveMT-PRIME-HERBRAND-KUMMER10 pts · DoneUpgrade potentially good to good reduction at fiveMT-PRIME-SPLIT-SEQUENCE10 pts · DoneThe ten-point finite enumeration over F_5MT-PRIME-SHAFAREVICH15 pts · DoneExclude order 11 and every prime order at least 17MT-PRIME-ISOGENY-CHAIN10 pts · BlockedConverge on a shared Mathlib and Tau Ceti pinMT-PIN-MIGRATION20 pts · DoneIntegrate finite and formal-immersion prime APIsMT-API-INTEGRATION10 pts · BlockedKernel-check Mazur's full torsion classificationMT-FINAL-ASSEMBLY15 pts · BlockedFinal challenge, exposition, provenance, and reproducibility auditMT-EXPOSITION-AUDIT5 pts · Blocked
Browse the graph as a dependency list
  1. Integrated baseline
    • Foundation node
  2. Finite-level endpoints
    • Needs MT-X11-JOIN
    • Needs MT-PRIME-ISOGENY-CHAIN
    • Needs MT-BASE-INTEGRATED
    • Needs MT-BASE-INTEGRATED
    • Needs MT-BASE-INTEGRATED
    • Needs MT-X0-MODULI, MT-X0-CUSPS, MT-X0-EISENSTEIN-ALGEBRA, MT-NERON-SPECIALIZATION
    • Needs MT-X0-MODULI
    • Needs MT-X11-JOIN, MT-X13-NONCUSP, MT-X18-NONCUSP, MT-O25-EXCLUDE, MT-O35-EXCLUDE, MT-O49-TOWER
  3. Shared algebraic geometry and isogenies
    • Needs MT-BASE-INTEGRATED
    • Needs MT-TC-A1-ORDER-SUPPORT
    • Needs MT-BASE-INTEGRATED
    • Needs MT-TC-A2-PRODUCT-FORMULA
    • Needs MT-BASE-INTEGRATED
    • Needs MT-TC-B1-COHERENT-COHOMOLOGY
    • Needs MT-TC-B1-COHERENT-COHOMOLOGY
    • Needs MT-TC-A3-DIVISOR-LINE-BUNDLE, MT-TC-C1-RELATIVE-COHOMOLOGY
    • Needs MT-TC-A3-DIVISOR-LINE-BUNDLE
    • Needs MT-TC-B2-RR-SERRE, MT-TC-C2-SYMMETRIC-POWERS, MT-TC-D1-PICARD-FUNCTOR
    • Needs MT-TC-D2-PICARD-REPRESENTABILITY, MT-TC-E0-PRODUCT-DIM
    • Needs MT-TC-C1-RELATIVE-COHOMOLOGY, MT-TC-E1-JACOBIAN-VARIETY
    • Needs MT-BASE-INTEGRATED
  4. Prime-level infrastructure
    • Needs MT-TC-E1-JACOBIAN-VARIETY, MT-X0-EISENSTEIN-ALGEBRA
    • Needs MT-NERON-BASE
    • Needs MT-NERON-COMPONENTS
    • Needs MT-BASE-INTEGRATED
    • Needs MT-FFGS-BASIC
    • Needs MT-FFGS-CONNECTED-ETALE, MT-NERON-COMPONENTS
    • Needs MT-BASE-INTEGRATED, MT-EC-ISOGENY-WEIL
    • Needs MT-X0-MODULI
    • Needs MT-X0-INTEGRAL
    • Needs MT-X0-INTEGRAL, MT-TC-E1-JACOBIAN-VARIETY, MT-TC-F1-ABEL-JACOBI
    • Needs MT-X0-JACOBIAN, MT-EC-ISOGENY-WEIL
    • Needs MT-X0-HECKE, MT-X0-INTEGRAL
    • Needs MT-X0-CUSPS, MT-X0-EISENSTEIN-ALGEBRA, MT-FFGS-OORT-RAYNAUD
    • Needs MT-BASE-INTEGRATED
  5. Mazur's prime-order argument
    • Needs MT-X0-MODULI, MT-X0-EISENSTEIN-QUOTIENT, MT-EC-ISOGENY-WEIL
    • Needs MT-PRIME-SEMISTABLE, MT-X0-CUSPS
    • Needs MT-PRIME-OUTSIDE-IDENTITY, MT-X0-EISENSTEIN-QUOTIENT, MT-NERON-SPECIALIZATION
    • Needs MT-BASE-INTEGRATED
    • Needs MT-BASE-INTEGRATED
    • Needs MT-PRIME-HERBRAND-KUMMER
    • Needs MT-BASE-INTEGRATED
    • Needs MT-PRIME-EISENSTEIN-SPECIALIZATION, MT-PRIME-DIVISION-FIELD, MT-PRIME-SPLIT-SEQUENCE, MT-PRIME-SHAFAREVICH
  6. Integration and hardening
    • Needs MT-BASE-INTEGRATED
    • Needs MT-FINITE-JOIN, MT-PRIME-ISOGENY-CHAIN, MT-PIN-MIGRATION
    • Needs MT-API-INTEGRATION
    • Needs MT-FINAL-ASSEMBLY, MT-X11-COSET, MT-CYCLOTOMIC-UNRAMIFIED

Current work-package frontier

Three packages, each tied to a real consumer.

Nested packages make large nodes navigable, but they do not create extra progress credit. The parent node still closes only when its reviewed API reaches the stated downstream boundary.

Current package12 allocated pts

WP-MT-TC-B1-COHERENT-COHOMOLOGY-COHERENT-CORE

Coherent sheaves and finite cohomology core

A cover-independent canonical K-linear H⁰/H¹ API, including H⁰/global-sections compatibility and coefficient-morphism and connecting-map linearity, is available to the proper-curve finiteness package.

Tauceti
Lane
Canonical curve cohomology to Jacobians
Parent node
Coherent cohomology of proper curves
Current package10 allocated pts

WP-MT-EC-ISOGENY-WEIL-WEIERSTRASS-GROUP-SCHEME

Canonical Weierstrass commutative group scheme

Starting from the checked over-base additions on D(x₁ - x₂) and D(B₁₂), their equality on the exact intersection, and the diagonal tangent comparison, glue their union; then add the infinity charts and coverage, prove the commutative group laws, and refactor MazurTorsion.XZeroFortyNine.orderFortyNineConcreteGroupSchemeInterface to consume the result without supplied [GrpObj (toOver E)] or CanonicalPointGroupLawCompatibility E shadow inputs.

Mixed
Lane
Represented X₀(N) vertical slice
Parent node
Cyclic subgroup quotients and classifying data

Open contracts

Exact Lean interfaces for proof and research.

Every card is an acceptance contract. There are 1 ordinary claims worth 10 points and 1 nonexclusive research intentions worth 18 points. Paused contracts are preserved in a separate section and cannot be claimed.

2challenges
OpenHigh risk

MT-O49-TOWER · 10 points

Bridge order 49 directly to the classified X_0(49) curve

An elliptic curve over Q has no rational point of exact order 49.

MazurCompiled
Estimated proof
1,000–3,000 Lean lines
Suggested route
Construct the X_0(49)(Q) moduli point directly from the cyclic subgroup generated by the exact order-49 point, prove it is noncuspidal, and apply the checked XZeroFortyNine.no_noncuspidal_correspondence_point/two-cusp classification. Do not first prove additivity of the explicit Velu point function unless the direct moduli bridge demonstrably fails.
Skills
elliptic curves · Velu isogenies · explicit modular curves
Lean acceptance boundaryChallenge.OrderFortyNine
DeclarationMazurTheorem.Challenge.no_rational_point_of_order_fortyNine
theorem no_rational_point_of_order_fortyNine
    (E : WeierstrassCurve ℚ) [E.IsElliptic]
    (P : (E⁄ℚ).Point) :
    addOrderOf P ≠ 49 := sorry

Imports

  • MazurTorsion.NumberTheory.XZeroFortyNineTransfer

Consumed by

  • MazurTorsion.rationalTorsion_orders_mem_cyclicOrders_of_remaining_obstructions

Destination

  • MazurTorsion.NumberTheory.XZeroFortyNineTransfer
  • MazurTorsion.XZeroFortyNine.rationalPoint_addOrderOf_ne_fortyNine
Depends on
Unlocks
Research OpenExtreme risk

MT-TC-A3-DIVISOR-LINE-BUNDLE · 18 points

Divisor-line-bundle dictionary

For the geometric order system of a smooth proper integral curve, prove the full invertible-sheaf/Picard comparison and identify divisor classes with the scheme Picard group. Checked code proves these two outputs are equivalent to the complete dictionary. Affinely, it constructs the actual tensor-additive tilde line bundles, a canonical Picard embedding with exact principal kernel, an unconditional range equivalence, and a full equivalence under exactly the reverse tensor-unit/local-rank-one comparison.

TaucetiCompiled
Estimated proof
1,000–6,000 Lean lines
Suggested route
Preserve the checked smooth-curve Dedekind chart compatibility, exact all-index raw overlap cocycle, generic `normalization_of_iso_cocycle`, derived `LineBundleCocycle.normalization`, and `moduleEffectiveDescentForOpenCover`. Package the concrete raw family as the required `LineBundleCocycle` and `DivisorCocycle`, using its exact-pseudofunctor-map overlap isomorphisms and pointwise all-index cocycle without an independent normalization field. Select or supply a universe-zero nonempty affine coordinate cover, then apply module effectivity and locality of invertibility to obtain the actual global divisor line bundles and their chart restrictions. Prove that these chosen globalizations are tensor-additive and coherently trivial on principal divisors; zero triviality then makes `L(-D)` an explicit inverse to `L(D)` without using `TensorInverseComparison X` for unrelated sheaves. Establish object separation, either from a checked fully faithful descent theorem or directly for the equalizer construction. Then derive overlap-compatible rational normalization from a global trivialization. The existing `TrivialDescendedLineBundleHasGlobalPrincipalWitness` equivalence turns that into principal detection, exact principal kernel, and the class equivalence. Prove Picard surjectivity and separately the global tensor-inverse comparison required by the stronger `Dictionary`. The weighted product formula remains the separately registered A2 prerequisite.
Skills
algebraic geometry · module localization · quasicoherent sheaves · divisor class groups

Parallel approaches are welcome for this research-open boundary.

Lean acceptance boundaryChallenge.DivisorLineBundle
DeclarationMazurTheorem.Challenge.divisorLineBundleDictionary
theorem divisorLineBundleDictionary
    (K : Type u) [Field K]
    (X : Scheme.{u}) [IsIntegral X] [IsNoetherian X]
    (π : X ⟶ Spec (.of K)) [IsProper π] [SmoothOfRelativeDimension 1 π]
    (S : TauCeti.AlgebraicGeometry.WeilDivisor.OrderSystem
      (TauCeti.AlgebraicGeometry.CodimensionOnePoint X)
      (Additive X.functionFieldˣ))
    (hord : S.ord = TauCeti.AlgebraicGeometry.SchemeWeilDivisor.orderAt) :
    Nonempty (MazurTorsion.AlgebraicGeometry.DivisorPicard.Dictionary S X) := sorry

Imports

  • MazurTorsion.Upstream.DivisorLineBundle
  • Mathlib.AlgebraicGeometry.Morphisms.Proper
  • Mathlib.AlgebraicGeometry.Morphisms.Smooth
  • TauCeti.AlgebraicGeometry.WeilDivisor.Scheme.Order

Consumed by

  • MazurTheorem.Challenge.divisorClassEquivPicard
  • MazurTheorem.Challenge.divisorPicardCoreData

Destination

  • MazurTorsion.Upstream.DivisorLineBundle
  • MazurTorsion.AlgebraicGeometry.divisorLineBundleDictionary
Depends on
Unlocks

Deliberately paused

Contracts preserved; speculative proof volume stopped.

Contracts remain immutable and compiled, but they are not claimable and receive no maintainer proof volume while the canonical foundation lanes are unfinished.

Paused12 pts retained

MT-X11-COSET

The five-coset bound on X_1(11)

The reverse X_1(11) model-to-Tate bridge, its discriminant certificate, the conditional cusp classification, and the conditional five-coset proof with Q=0 are checked. The node remains open until MT-X11-JOIN supplies the unconditional order-11 exclusion and the immutable Challenge bridge compiles. The direct five-isogeny Selmer calculation remains a partial fallback.

Paused26 pts retained

MT-X13-NONCUSP

Classify the noncuspidal rational points on X_1(13)

Show that the explicit genus-two order-13 model has no rational affine point with x different from 0 and -1. The checked primitive split descent clears all three cusp factors, derives the two remaining cubic coefficient identities, proves both conic parameters odd, and forces k to be -4 or 4. Its global rational-point elimination, and hence the genuine Mazur--Tate Jacobian/rank-zero conclusion, remain open.

Paused18 pts retained

MT-X18-NONCUSP

Classify the noncuspidal rational points on the order-18 curve

Show that the explicit genus-two order-18 model has no rational point with x different from 0 and 1. The checked primitive split descent derives the two remaining cubic coefficient identities, proves both conic parameters odd, and forces k to be -8, -4, 4, or 8. Classification of these two explicit split covers, equivalently a genus-two Jacobian rank-zero certificate or another complete descent, is still required; the Challenge remains open.

Paused16 pts retained

MT-O25-EXCLUDE

Exclude exact rational order 25

Prove that no rational point on an elliptic curve over Q has exact additive order 25. The checked Tate recurrence computes (n+2)P from index n and proves every secant denominator through 13P nonzero from exact order 25. Explicit square/cube normalized coordinates through 13P reduce x(13P)=x(12P) to the cuspidal factor b-c times one fixed 234-term polynomial of total degree 40. The arbitrary-curve consumer retains b, c, and b-c nonzero together with the twelfth-power discriminant scale. Classifying rational solutions of that explicit noncuspidal factor, directly or after a checked birational reduction, remains open.

Paused14 pts retained

MT-O35-EXCLUDE

Exclude exact order 35 with the shared formal-immersion engine

Use the explicit optimal elliptic quotient X_0(35)/w_5 and Mazur's squarefree-level formal-immersion criterion at auxiliary prime 11. The source three-descent and Eisenstein ideal-support calculations prove the fixed explicit curve model has rank zero and finite rational point group. The represented modular classifying map and chart identification, the characteristic-eleven cusp local-ring generator and unit calculation, the abelian-variety identification, and Atkin--Lehner specialization inputs remain open.

Paused20 pts retained

MT-CYCLOTOMIC-UNRAMIFIED

Cyclotomic unramified character extensions

Close the inherited locally-primary pseudo-unit reciprocity Challenge and preserve the checked cyclotomic infrastructure as an independent release obligation. The checked Hilbert-94 layer exposes the actual equivariant capitulation map, a nontrivial Galois-stable exponent-p kernel, and a division-field consumer. The chosen proof of Mazur's theorem does not consume this result.

How progress is scored

Four gates. One weighted ledger.

A node earns no theorem-progress credit for a statement alone. A proof node earns 70% for an isolated kernel proof, 85% after API review, and 100% only after a downstream consumer compiles. Infrastructure earns 40% when its definitions compile, 70% after mathematical sanity checks, and 100% after a real downstream consumer compiles. The headline is the weighted sum.

  1. 01
    Statement

    The formal declaration faithfully matches the mathematics.

  2. 02
    Kernel proof

    Lean accepts it without project-specific axioms or placeholders.

  3. 03
    API accepted

    Definitions pass mathematical sanity checks and review.

  4. 04
    Integrated

    A named downstream consumer compiles against the result.

What 17.2% does—and does not—mean

It is an effort-weighted planning estimate, not a theorem of project management. The denominator is uncertain because Jacobians, integral modular curves, Néron models, and the Eisenstein quotient do not yet share a tested Lean spine.

The ≈18% ecosystem-ready figure is deliberately shown separately. It counts work that may be reusable from Lean Pool, Tau Ceti, FLT, and other audited repositories, but it earns integrated credit only after porting and consumer tests. Percentages will move as interfaces reveal the real work.

Work-package allocations only divide a stable parent node into reviewable steps. They never add to the denominator and never earn credit independently. Paused contracts keep their weight and statement while remaining unavailable for claims.

Join the programme

Pick a boundary. Prove it. Connect it.

Contributors get an exact declaration, pinned dependencies, a named consumer, and review criteria. Maintainers coordinate the shared architecture so independent work composes.