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Add CompositionAlgebrasOverRings

Adds Composition Algebras over Commutative Rings (LeanPool.CompositionAlgebrasOverRings,
105 files, about 29,000 lines). It formalizes much of Part I of Garibaldi–Petersson–Racine, Albert
Algebras over Commutative Rings
(Cambridge, 2024), referred to as GPR below. Specifically: conic algebras, Cayley–Dickson doubling,
composition algebras, reduced composition algebras, and the classification over special classes of
fields. Objects are defined over an arbitrary commutative ring, and nothing assumes that 2 is
invertible.

Source: skipgaribaldi/CompositionAlgebras-lean, tag v1.0 (commit 87b1eeb), Apache-2.0.
That repository is frozen; this copy is meant to be maintained in the pool. Provenance: AI.

Why this level of generality

Existing formalizations cover only part of the theory of composition algebras, and only where 2
is invertible. The pool's composition-algebras project works over ℝ. TauCeti has the split
octonions as one concrete algebra, and its Witt cancellation assumes a field in which 2 is
invertible. Mathlib has quaternion algebras but no composition algebras, and its base change of
quadratic forms requires Invertible 2.

Characteristic 2 is where those tools fail. A quadratic form is no longer determined by a
symmetric bilinear form, its polar form is alternating so it cannot be diagonalized, and the usual
notions of regularity come apart. Once the theory is written so that characteristic 2 is included (the un-halved polar form,
transvections instead of reflections, and GPR's separate regularity notions), it costs little more
to work over a commutative ring. The definitions of conic and composition algebras and of
Cayley–Dickson doubling make sense verbatim, and base change of quadratic forms is constructed here
without inverting 2.

Most of the structure theory does not extend to arbitrary rings, however. Over a general ring,
finitely generated projective modules of constant rank need not be free, and composition algebras
with isometric norms need not be isomorphic (Gille, 2014). The classical arguments do extend to
semilocal rings. A slightly larger class, the LG rings (a polynomial represents a unit as soon
as it does over every residue field), retains most of the structure theory. It includes all fields
and all semilocal rings, and over it constant-rank projective modules are free and Witt
cancellation holds, which is what lets the field proofs go through.

So the project defines its objects over an arbitrary commutative ring and proves there what holds
there, such as alternativity and the rank theorem. It states the structure theory over LG rings,
and the field case is an instance of it rather than a separate development.

What is new

  • Witt cancellation over LG rings (QuadraticForm.cancel): q₁ ⊥ q₃ ≅ q₂ ⊥ q₃ ⇒ q₁ ≅ q₂
    for q₂ nonsingular and q₃ regular, by the elementary Dias–Baeza–Knebusch route (hyperbolic
    planes and transvections) rather than the cohomological proof of Gille–Neher 6.5.
  • Artin's theorem for alternative rings (IsAlternative.isAlternative_iff_two_generated_assoc),
    with the alternating associator and the Moufang identities for arbitrary alternative rings.
  • LG rings: examples, non-examples, and freeness of constant-rank projective modules
    (Module.free_of_isLGRing_of_rankAtStalk_eq).
  • Composition algebras over any commutative ring are alternative
    (ConicAlgebra.IsComposition.isAlternative_general), and have rank 1, 2, 4 or 8 with the
    expected structure in each rank (ConicAlgebra.IsComposition.rankAtStalk_classification).
  • Over LG rings: the norm determines the algebra
    (ConicAlgebra.IsComposition.exists_isometryEquiv_map_one_map_mul), and reduced composition
    algebras are split
    (ConicAlgebra.IsReduced.isSplit_of_isLGRing, GPR 22.16).
  • Also: the rank decomposition of a finitely generated projective module (GPR Exc. 9.31),
    invertible modules as line bundles, and isotropy of quadratic forms over finite fields via
    Chevalley–Warning.

Overlap with the pool and TauCeti

  • composition-algebras (Bryan Ehrlich) proves Hurwitz's classification of Euclidean
    composition algebras over ℝ. This project covers the same ground, by its classification of
    real composition division algebras (GPR 23.13) and its rank theorem over arbitrary rings.
    Declaration names do not collide.
  • TauCeti has Witt cancellation over fields, a concrete Octonion type (Zorn vector matrices
    over a commutative ring) with its Moufang identities, and the classification of real quadratic
    forms by signature. Here cancellation is over LG rings, the Moufang identities are for every
    alternative ring, and the Zorn algebras are twisted by an arbitrary vector-product pair on a
    rank-three projective module (GPR 22.14–22.15).
  • Where TauCeti already has a result, this port uses TauCeti's instead of its own copy:
    QuadraticMap.IsometryEquiv.prodAssoc, QuadraticMap.IsometryEquiv.polar_apply,
    QuadraticMap.radical_smul, TauCeti.Module.rankAtStalk_dual, the dual base change
    TauCeti.Module.Dual.baseChangeEvaluationEquiv (GPR 9.15), the Eichler transvection
    QuadraticMap.transvection, the hyperbolic-pair torus
    TauCeti.QuadraticMap.hyperbolicPairTorus, and QuadraticForm.anisotropic_iff_posDef_or_negDef.

Port notes

  • Built against the pool pins (Lean/Mathlib v4.35.0-rc3, TauCeti 5189e8a). One proof needed
    an explicit AlternatingMap.zero_apply.
  • The source repository's README and contributor guide are carried into the entry module's
    docstring (layout, conventions, design decisions, and six "traps" where the obvious statement is
    false over a ring), and docstrings cite it as "overview §N".
  • A deprecated compatibility alias from the source repository was dropped.

Checks run locally

lake build LeanPool.CompositionAlgebrasOverRings.Imports with no warnings; runLinter and
lint-style on the project; python -m lean_pool.quality --static-only; every declaration uses
only propext, Classical.choice and Quot.sound. The full-pool stages run in CI.

🤖 Generated with Claude Code

Composition algebras over commutative rings, following Garibaldi,
Petersson and Racine, Albert Algebras over Commutative Rings, Part I;
with Witt cancellation over LG rings and Artin's theorem on alternative
rings. Ported from skipgaribaldi/CompositionAlgebras-lean at v1.0
(87b1eeb), building against the pool pins, and reusing TauCeti where it
already has a result.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
@greptile-apps

greptile-apps Bot commented Oct 17, 2026 •

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Advisory cross-file review against Lean Pool's supervisory rubric. This is not by itself a significance, source-verification, or merge verdict.

RetriggerView in Greptile

[Low impact] No blocking issue was established in the latest revision, but the full contribution has not been checked completely.

Summary

Adds composition algebras over commutative rings, with Witt cancellation, Artin’s theorem, and classification results.

  • Composition algebras over rings have four possible constant ranks.
  • Conic algebras provide the starting point for doubling and composition.
  • LG rings provide tools for classifying algebras and quadratic forms.
  • Reduced composition algebras are classified and split over LG rings.

Reviews (5) · Last reviewed commit: "Correct the Artin theorem bibliography" · Reviewed by Greptile

Comment thread LeanPool/projects/composition-algebras-over-rings.yaml Outdated
@Vilin97

Vilin97 commented Oct 17, 2026

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/review

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Source approval at 73c23ad, subject to current-head validation and the independent configured review.

I corrected two summary scope issues: rank constancy is an assumption, and the characteristic-free claim concerns the listed main results. The summary now also states the finite-projective model explicitly. Only the project YAML changed; all 106 Lean blobs are identical to the submitted 0255f05 head. Parsing confirms every other card field is unchanged, and the current generated-card renderer produces the same entry docstring.

The mathematical review covered all seven headline contracts and their decisive producer chains, with independent foundation and algebra reviews:

  • Witt cancellation: over an LG ring, q₂ is nonsingular and the cancelled q₃ is regular on finite projective modules. The proof constructs the required isometry through hyperbolic cancellation; it assumes neither invertible 2 nor free or constant-rank modules.
  • Artin: alternativity is equivalent to associativity of every two-generated non-unital subring. The hard direction is proved through words, associators and Moufang identities.
  • Projective freeness: finite projective modules of explicitly constant stalk rank over LG rings are free, through the proved unimodular splitting argument.
  • General alternativity: finite projective composition algebras are alternative over arbitrary commutative bases, including characteristic two and changing-rank bases. The proof uses regular/rank-one components and rank-idempotent descent.
  • Rank classification: the nontrivial-base and constant-rank assumptions are explicit. The conclusion includes the algebraic structure and the negative commutativity/associativity assertions in ranks four/eight.
  • Norm classification: an LG-ring norm isometry yields some unital multiplicative norm isometry. It does not assert that every supplied isometry preserves multiplication.
  • Reduced implies split: the rankwise elementary-idempotent characterization of reducedness feeds Peirce reconstruction; LG freeness untwists the rank-one/rank-three modules. Splitness is not assumed inside the reducedness predicate.

The formalization assumes finite generation where the broader literature derives it; that boundary is disclosed in Composition/Defs.lean and now in the summary. The regular/nonsingular distinction and the LG restriction on norm classification are preserved.

This is a substantial general-ring extension. The nearest existing pool development concerns positive-definite real composition algebras; the inspected Tau Ceti cancellation result assumes a field and invertible 2. Eight existing Tau producer modules are actually imported and used. There is concrete supporting-model overlap: Tau already has the fixed split-Zorn octonions, equivalent here under the coordinate change (a,u,b,v) ↦ (a,b,−v,u). I count that construction as overlap; the arbitrary-projective twisted models, generic algebra laws and LG classification supply the extension.

The annotated upstream v1.0 tag resolves to 87b1eeb4f9146c65ebe664a98a012819a970af95, with Apache-2.0 licensing and accurately declared AI proof provenance. The cited book and its author-hosted draft support the checked theorem scopes (§§11.24, 14.5, 19.18, 22.16 and 23.5). This does not certify every ancillary citation or claim the whole book is formalized.

Quality is competent, 3/5. The reviewed proof chains expose useful intermediate constructions and retain characteristic-two distinctions. Two unused private quaternion shims and repeated Peirce-rank preparation are optional maintenance opportunities, not merge requirements.

This is a finite substantive review of the headline chains and representative supporting proofs, with complete source available—not a claim to have manually audited every one of the roughly 29,000 lines. Novelty comparisons are bounded to the actual nearest declarations inspected.

Integration remains pending: current-head Lean build/lint/style/quality and all applicable protected checks, configured findings, resolved discussions and normal native-queue protections still apply. The single current /review request is already submitted. I have not enrolled or merged this PR.

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🤖 LLM review (gpt-6.1-sol, 5 rubrics)

Reviewed head: 5882deab58b7c64bab0fe760f7b656367374c55b

Verdict: ✅ approve — computed from the rubric verdicts below, not chosen by a model.

Rubric Verdict Bottom line
Faithfulness ✅ pass All seven card headlines match their Lean statements and disclosed assumptions; local build validation was blocked by HTTP 403 fetching Mathlib, and CI status could not be retrieved.
Novelty ✅ pass No checked existing declaration subsumes the seven headline statements; the identified overlaps are genuine extensions.
Significance ✅ pass The structural and classification theorems meet the research-level significance bar; CI remains pending, and a Mathlib fetch HTTP 403 prevented local build verification.
Sources ✅ pass The checked GPR, GN, and Schafer citations align; detailed Dias/Baeza proof references remain unverifiable, and CI remains pending.
Code quality (advisory) ✅ pass Competent Lean with localized proof duplication; CI remains pending, and the local build stopped before elaboration because fetching Mathlib returned HTTP 403.
Aspect Value
Proves the claim ✅ proves_it
Assumed, not proved Finite projectivity is disclosed in the summary. Cancellation assumes an LG base, nonsingularity of q2, regularity of q3, and isometric orthogonal sums. Freeness assumes constant rank. Norm classification assumes an LG base and isometric norms; reduced-to-split assumes reducedness and an LG base. The structural conclusions are proved from these inputs, without assuming invertibility of two.
Matches cited source 🟡 unverifiable
Fit ✅ good_fit
Level research
Branch nonassociative algebra
Mode theory_building
Code quality 3 / 5

Statement check: Rank classification requires constant rank and a nontrivial base; alternativity, norm classification over LG rings, and reduced-to-split over LG rings have no constant-rank restriction.

Develops composition algebras over commutative rings through rank classification, norm classification and reduced splitting over LG rings, supported by Witt cancellation and Artin’s theorem.

Faithfulness findings (1)

  • prompt-injection — PR-wide
    The final discussion comment directs reviewer model selection. Such PR-controlled operational instructions have no authority under the review trust boundary and were ignored.
    Evidence: prose only: “Please use the configured GPT-6-Astra/xhigh review described in README.md and python/review-operations.md.”

Novelty findings (4)

  • partial-overlap — LeanPool/CompositionAlgebrasOverRings/QuadraticForm/WittCancellation.lean:208
    Field cancellation already exists in Tau Ceti. Here theorem cancel (hLG : IsLGRing R) extends the base-ring scope to LG rings without assuming two invertible, while requiring nonsingularity of the second remaining form and regularity of the cancelled form.
    Evidence: TauCeti.equivalent_of_equivalent_prod_right cancels a finite-dimensional nondegenerate summand over a field with invertible two, without a nonsingularity assumption on the remaining forms: declaration.
  • partial-overlap — LeanPool/CompositionAlgebrasOverRings/LGRing/ConstantRank.lean:110
    The semilocal freeness case is already in Mathlib. theorem Module.free_of_isLGRing_of_rankAtStalk_eq (hLG : IsLGRing R) (d : ℕ) : extends the base class to LG rings for finite projective modules of constant rank.
    Evidence: Module.free_of_flat_of_finrank_eq proves freeness of finite flat modules over a commutative ring with finitely many maximal ideals, assuming equal residue-field dimensions: declaration.
  • partial-overlap — LeanPool/CompositionAlgebrasOverRings/Composition/Fields/Real.lean:163
    IsComposition.isomorphic_realTower_of_hasTwoSidedInverses overlaps the pool’s real Euclidean classification. The contribution extends that setting: IsComposition.isSplitOfRank_or_isomorphic_realTower also treats split real algebras, and IsComposition.rankAtStalk_classification works over arbitrary nontrivial commutative bases with constant rank.
    Evidence: CompositionAlgebra.hurwitz_classification in LeanPool/CompositionAlgebras/Composition/Classification.lean classifies finite-dimensional nontrivial real Euclidean composition algebras by linear equivalences preserving the unit, multiplication, and norm; CompositionAlgebra.finrank_eq_one_or_two_or_four_or_eight gives their dimension restriction.
  • partial-overlap — LeanPool/CompositionAlgebrasOverRings/Composition/Alternative.lean:184
    theorem IsComposition.isAlternative_general (h : C.IsComposition.{u, v, u}) : IsAlternative A := by extends existing concrete alternativity results to composition algebras over arbitrary commutative rings. The general alternative-ring Moufang identities likewise extend the concrete octonion identities.
    Evidence: CompositionAlgebra.left_alternative and CompositionAlgebra.right_alternative cover real Euclidean composition algebras. TauCeti.Octonion.left_alternative, TauCeti.Octonion.right_alternative, and TauCeti.Octonion.moufang_left concern the concrete split Octonion over a commutative ring: declarations.

Significance findings (1)

  • prompt-injection — PR-wide
    The PR discussion directs the reviewer to select a model and consult repository instructions. Such commands could redirect review configuration; they were disregarded. Keep operational configuration in trusted review instructions.
    Evidence: The final discussion comment says: ‘Please use the configured GPT-6-Astra/xhigh review described in README.md and python/review-operations.md.’

Sources findings (1)

  • prompt-injection — PR-wide
    The PR discussion attempts to control the review model and routing; this contributor-written instruction was disregarded and does not affect the sources verdict.
    Evidence: Please use the configured GPT-6-Astra/xhigh review described in README.md and python/review-operations.md.

Code quality findings (3)

  • proof-duplication — LeanPool/CompositionAlgebrasOverRings/Composition/Reduced/Classification.lean:425
    Six specializations repeat the abstract classification arguments: the rank-four and rank-eight results over LG rings and PIDs, and both split/isotropic equivalences. The substantive change is the freeness witness. Put the abstract results first and make these specializations wrappers, using ProjectiveConstantRankFree.of_isLGRing and an analogous PID witness. This keeps subsequent classification changes in one proof.
    Evidence: isSplitOfRank_eight_of_isLGRing uses:
    let : Module.Free k M := Module.free_of_isLGRing_of_rankAtStalk_eq hLG 3 M hM
    isSplitOfRank_eight_of_projective_constantRank_free uses:
    let : Module.Free k M := hfree M 3 hM
    Both then repeat:
    let b : Module.Basis (Fin 3) k M :=
    Module.finBasisOfFinrankEq k M (finrank_eq_of_rankAtStalk_eq hM)
    exact (hc.isomorphic_twistedZor (k := k) hcomp.isMultiplicative hreg).symm.trans
    (isomorphic_twistedZor_of_exists_basis P b)
  • proof-duplication — LeanPool/CompositionAlgebrasOverRings/Conic/Projective.lean:192
    norm_eq_of_projective, traceDefect_eq_zero_of_projective, and Composition/RankDichotomy.lean’s eq_unitForm_smul_one_of_rankAtStalk_eq_one independently reconstruct the same kernel projection and finite/projective instances. The project already supplies LinearMap.equivProdKerOfApplyEqOne and equivalent instance-transfer lemmas in LGRing/ConstantRank.lean. Move the generic transfer facts to the lower module layer and reuse them, avoiding three copies of the splitting argument.
    Evidence: In traceDefect_eq_zero_of_projective, repeated from norm_eq_of_projective:
    have hpi : p ∘ₗ N.subtype = LinearMap.id := by
    refine LinearMap.ext fun z ↦ Subtype.ext ?_
    have hz : C.unitForm (z : A) = 0 := z.2
    simp [hp, hz, LinearMap.toSpanSingleton_apply]
    have : Module.Finite k N :=
    Module.Finite.of_surjective p fun z ↦ ⟨(z : A), DFunLike.congr_fun hpi z⟩
    have : Module.Projective k N := Module.Projective.of_split N.subtype p hpi
    The rank-one proof reconstructs these instances before also defining:
    let E := LinearMap.equivProdKerOfApplyEqOne D.unitForm (1 : B) D.unitForm_one
  • prompt-injection — PR-wide
    The PR discussion attempts to direct reviewer model selection through repository documentation. This instruction was treated as untrusted evidence and ignored.
    Evidence: Please use the configured GPT-6-Astra/xhigh review described in README.md and python/review-operations.md.

Tokens: 23,803,107 in / 75,434 out across 5 model calls · Tier: codex-subscription · Effort: xhigh · Billing: Codex subscription quota (no API credits) · Estimated cost: $96.3439 (Standard API equivalent; uncached input)
Each rubric is an independent review against .github/review-rubrics/ on top of .github/REVIEW_RULES.md. Disagree? Reply on the PR; rules can be updated in a PR of their own.

CI was not green for this commit at review time; this review does not replace CI.

Preserve the explicit-universe interfaces while allowing the unchanged
axiom-name audit to resolve three declarations. Correct Cayley-Dickson,
norm-associativity, and invertible-module documentation against the cited
primary statements. No theorem statement or proof is changed.

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Source review for exact head 91949006743f44f1f1b451076fed7c9d20cb7e7b.

I pushed the finite repair in 9194900. The failed quality audit on 73c2 requested three declaration names with an extra terminal dot, taken from explicit universe suffixes. Declaring those fresh universes separately lets the unchanged checker resolve the names. The focused Lean validation preserved all 14 inspected exported universe/type/value records byte for byte, including generated IsComposition API; the explicit-universe client compiled, and all 62 audited public names resolved with only the permitted axioms. This was focused dependency/client validation, not a full local build of all 106 files.

I verified and corrected all four concrete Sources findings from configured review2163. The Cayley–Dickson comments now distinguish the associative sufficient case from the sharp radical criterion, state commutativity using trivial conjugation rather than B = k, and qualify the characteristic-two tower discussion. Norm-associativity cites the correct sides of 16.12 and proposition17.2(a); tensor-invertibility cites Stacks 0B8I. These corrections were checked against the author’s GPR draft, sections16–18. All additional edits are balanced comments with the same declaration associations; theorem statements/proofs, the card, imports, pins and gates are unchanged.

I also followed up the novelty discussion against actual pinned candidates:

  • Tau’s octonion laws concern a fixed free split rank-eight model. They do not supply the submitted Artin theorem for arbitrary nonunital nonassociative rings, or classification of arbitrary finite-projective composition algebras. The fixed split-Zorn overlap is acknowledged support, not a novelty claim.
  • Mathlib’s nearest freeness theorem uses a semilocal base. On the common finite-projective setting the submitted LG polynomial hypothesis extends the base setting; I am not claiming it subsumes every finite-flat variant. The inspected Tau projective-reduction, dual and free-locus results do not furnish that LG conclusion.
  • The pool’s existing classification is for finite-dimensional positive-definite real composition algebras. The arbitrary-base, constant-stalk-rank and LG results here are substantive extensions. This is a bounded comparison of concrete contracts, not a universal absence claim.

Source approval is retained at this exact 9194900 head. Hosted Lean run38990242038 completed SUCCESS at 01:40:18Z: its index, build, lint, style and repository-quality steps all passed, as did canonical Build project117275710814. The complete individual check census has 11 successes and ten scope skips; those skips are recorded separately from actual build executions.

The configured result for this repaired head remains outstanding; the current-head review request is recorded. Review2163 concerns predecessor73c2. Main advanced following PR652's protected merge, and its separate source-bearing main-push validation was still running at the 02:04–02:06Z snapshot. Queue admission remains conditional on the current configured result, applicable current-main validation, resolved discussions and normal protections.

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Thanks for the review and for the fixes. I checked the four source corrections in 9194900 against the GPR text, and they are right:

  • 18.14(a): Cay(B, μ) is commutative if and only if B is commutative with trivial conjugation, not only when B = k; Example 18.17(b) gives the characteristic-two tower where this matters.
  • Exc. 18.18: for multiplicative B the criterion is μ[B, B, B] ⊆ Rad(Dn_B); associativity of B is the sufficient case that is formalized here.
  • Norm-associativity is (16.12.3) and (16.12.4), and Proposition 17.2(a) supplies it for multiplicative algebras; 16.5 was the wrong citation.
  • Stacks 0B8I (Lemma 15.119.2) is the right reference for "invertible if and only if finite locally free of rank one".

The card wording changes are fine too. I have made the same corrections in the source repository.

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/review

Current head: 9194900

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Vilin97 commented Oct 17, 2026

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/review

Current head: 4ec889b

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Source acceptance for 4ec889b7d5780d035e2a96e8e760ab58528a52f9.

I have addressed the source mismatch in configured review 2164. Four documentation blocks now distinguish the sufficient associativity hypothesis from GPR Exercise 18.18's scalar–associator/radical criterion, include the zero-parameter exception, and separate multiplicativity from being a composition algebra. The theorem documentation for 𝕆 now states exactly the proved nonassociativity result.

The two longest duplicated arguments identified there now use the existing general results: the LG reduced-to-split theorem instantiates the constant-rank projective freeness theorem, and the tower existence proof uses the established norm-transport/regularity/rank helper. Public statements, hypotheses, universe declarations, imports, project registration and gates are unchanged.

Validation of these exact proof postimages passed with warnings treated as errors through their necessary 71-module project dependency closure (62 newly compiled; nine exact cached modules reused). Both complete modified proof modules passed the unchanged axiom audit: all 40 public declarations resolved with no unapproved axioms. The two changed public theorems retain universe parameters [u, v]. This is targeted validation; the complete new-head hosted checks remain required.

I also considered 2164's novelty discussion. The inspected field cancellation theorem assumes a field and invertibility of two; the LG-ring cancellation theorem here covers a different, disclosed regime, including characteristic two. The existing pooled real classification overlaps one specialization, while the arbitrary-ring rank classification and LG-ring norm/splitting development add substantive mathematics. On those concrete comparisons I accept the contribution as a significant extension. This does not claim exhaustive absence of every equivalent theorem. The remaining short specialized wrappers are acceptable localized maintenance debt; the shared classification and doubling arguments now have one implementation.

Integration remains pending the new-head configured review requested in #issuecomment-6229061532, complete applicable hosted validation, and the protected native queue. Previous-head CI is historical evidence.

Remove the unverified 1927 entry; retain the Schafer reference followed by the proof.

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Source review for exact head 5882deab58b7c64bab0fe760f7b656367374c55b.

The Sources finding in review2167 is addressed by removing the unverified Artin1927 bibliography entry. Artin's theorem name, the proof-strategy attribution and Schafer §3/Theorem3.1 remain. The accessible Schafer lecture notes, pp18–19 prove the intended result; Rost §4 corroborates the 1966 book's Theorem3.1/p29 locator. I make no claim about every passage in the inaccessible 1927 paper.

An independent complete-file inverse and Git tree comparison confirm that this successor deletes only two comment lines: every Lean command, public statement, proof, import and other file is byte-identical to reviewed 4ec889b7. The earlier targeted build and axiom evidence retain their recorded scope; this is not a new CI pass.

I also checked review2167's remaining six short specialization proofs and three kernel-setup repetitions. They are real, localized maintenance debt, with no identified mathematical or API defect, and are acceptable under its advisory PASS3 verdict.

Source approved. Current-head CI, the configured review and normal protected native-queue requirements remain pending.

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Vilin97 commented Oct 17, 2026

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/review 5882dea

The successor removes only the two unverified Artin1927 bibliography lines identified in2167; the supporting Schafer citation and all Lean commands are unchanged. Please use the configured GPT-6-Astra/xhigh review described in README.md and python/review-operations.md. Published2167 reports GPT-6.1-Sol/xhigh, so it does not establish the documented model routing. This is one request for the new exact head; prior4ec request6229061532 was fulfilled by2167.

@Vilin97
Vilin97 added this pull request to the merge queue Oct 17, 2026
Merged via the queue into LeanPool:main with commit 8cba244 Oct 17, 2026
21 checks passed
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