Euler-Reduced Tjurina Floors for Osculating-Absorbing Gauss Fibres
Corrected version of a screened paper. Not peer reviewed. Screening record
Let h in C[[x_1,...,x_d]] have order at least s+1 and finite Tjurina algebra. Euler cancellation replaces h, without changing its Tjurina ideal, by a generator of order at least s+2. A finite-jet generator count then gives tau(h) at least E_{d,s}, the maximum over K of binom(d+K,d)-d binom(d+K-s,d)-binom(d+K-s-2,d). For plane germs this is the exact universal floor floor((3s^2+4s-3)/4), attained by classical ordinary multiple-point families. Applied to a point-span s-osculating-absorbing reduced fibre of the Gauss map in the complete O_X(m) embedding, the result gives length(Gamma_eta) at least E_{d,s} binom(d+m,d). For surfaces, a prescribed-jet construction realizes equality at an explicit sufficient degree. The work is over C; the higher-dimensional floor need not be sharp, the degree threshold is not claimed minimal, and no exhaustive priority, human peer-review, or formal-verification claim is made.
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Cite this paper
Lluis Eriksson (2026). Euler-Reduced Tjurina Floors for Osculating-Absorbing Gauss Fibres. AIRR.SCIENCE, ARR-2026-5XEX8EX0629R997Y, v2. https://airr.science/papers/ARR-2026-5XEX8EX0629R997Y/versions/v2/
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Revision statement
Minor revision. Corrects the canonical source hash after Git line-ending normalization and records the preserved LF byte stream; mathematical content is unchanged.
Verification record
- Frontier-model screening
- Not assessed
- Source integrity
- Pass
- Bibliographic integrity
- Partial
- Reproducibility
- Partial
- Lean 4
- Not applicable
Recorded under ARR-VERIFY-1.0. AIRR verification and screening are not peer review.
AI assistance statement
OpenAI Codex assisted with theorem exploration, proof development, adversarial repair, primary-literature and public-corpus triage, exact replay code, drafting, LaTeX production, visual QA, packaging, and deposit preparation. Separate Codex referee tasks audited exact source snapshots. These AI checks are not human peer review, formal verification, independent reproduction, or priority certification; the author remains responsible for every claim.
Frontier-model screening
Status: not_assessed. Any listed reports correspond to this exact version under ARR-SCREEN-1.0; no absent assessment is represented as a pass.
Model assessments and review context
- Distinct models
- 2
- Range
- 3.40–3.75
- Method
- bounded capability-weighted mean · exact version only
Limited evidence · 1/2 benchmark matches. This is an evidence description, not a probability of correctness.
One provider; shared blind spots possible; Fresh blinded review context not documented for every model; Benchmark match incomplete; Adverse reports or unresolved objections require editorial disposition
OpenAI · gpt-5.6-sol · High · unknown · review context: unknown3.75
Recommendation: Minor Revision · Material objections: 0
This exact v2 PDF presents a sound Euler-reduced generator count for Tjurina algebras and correctly optimizes it; in dimension two it recovers the classical sharp minimum floor((3s^2+4s-3)/4) for every isolated germ of order at least s+1. The surface construction plausibly and coherently realizes the product floor on a finite Gauss fibre using prescribed contact-determined jets, incidence smoothness, and an unisolvent support. The main mathematical claims survived direct checks. Minor revision is warranted because Gauss-fibre finiteness is implicit and the replay is neither dependency-complete nor literally byte-reproducible across platforms, despite the manuscript's byte-comparison language.
- Correctness confidence
- Euler cancellation preserves the Tjurina ideal, the truncated image-dimension estimate is valid, the plane maximization and exact families check, and the prescribed-jet surface construction is coherent. No counterexample to a main theorem was found.
- Rigor
- The local bound is self-contained and the global proof explicitly controls interpolation, off-support smoothness, the Gauss fibre, absorption, and length. The finiteness of the Gauss fibre for a smooth non-linear hypersurface is used implicitly rather than stated or justified.
- Novelty
- The sharp plane Tjurina minimum and attaining families are classical; the plausible novelty is the elementary all-germ lower count and its absorbed Gauss-fibre synthesis. Targeted primary-source checks confirm the classical boundary but do not establish exhaustive priority.
- Significance
- The work converts one Euler-forced order gain into an exact per-support plane bound and a simultaneous sharp global surface realization, a meaningful bridge between local singularity invariants and Gauss-fibre geometry.
- Reproducibility
- After installing the undeclared SymPy dependency, all finite exact checks passed. Fresh combined JSON did not match committed bytes because runtime platform and Python version are embedded; deleting only the runtime object produced exact agreement, so the mathematics reproduced but the advertised byte stability did not.
Strengths
- Lemma 2.1 uses Euler's identity exactly where characteristic zero is needed, raises the residual generator from order s+1 to s+2, and proves equality of the original and reduced Tjurina ideals.
- Theorem 2.2 bounds the image of each truncated generator separately; possible syzygies only strengthen the quotient lower bound, so no genericity or tangent-cone hypothesis is hidden in the count.
- The plane quadratic optimization was checked algebraically, and the cited primary source explicitly gives the same classical minimum and the same even/odd attaining families.
- Theorem 5.1 tracks enough jets for contact determinacy, uses separator products to prescribe them simultaneously, and identifies the reduced Gauss fibre with the singular locus of the tangent section.
- The final equality combines exact local Tjurina lengths with the separately verified support floor rather than treating finite computations as a universal proof.
Weaknesses
- Theorem 4.2 does not explicitly explain why the Gauss fibre is finite; for a smooth non-linear hypersurface this follows because the Gauss pullback of O(1) is the ample O_X(deg X-1), but the length decomposition relies on that fact.
- The higher-dimensional optimized number E_d,s is only a generator-count lower bound; sharpness and geometric realization are established only for d=2.
- The novelty claim is necessarily narrow because the plane minimum and families are classical and the elementary local estimate may have prior commutative-algebra formulations.
- The replay package omits a dependency specification for SymPy and embeds runtime metadata in the combined JSON, defeating literal cross-platform byte identity.
Potential errors
- The manuscript says fresh replay JSON is compared byte-for-byte with the committed result. In this execution the mathematical payload matched exactly after deleting the runtime object, but the full bytes differed because the stored file records Windows/Python 3.12.6 and the fresh file Linux/Python 3.12.14.
Strong novelty candidates
- The Euler-reduced truncated-generator lower bound for arbitrary isolated hypersurface germs, especially its optimized higher-dimensional asymptotic, is a plausible novelty candidate subject to a fuller commutative-algebra search.
- The synthesis turning osculating absorption into an exact sharp plane Gauss-fibre length floor with simultaneous proper-span surface extremizers is the strongest candidate for a new contribution.
- The explicit prescribed-jet global realization at the smallest support permitted by absorption appears distinct from the classical local computation, though priority was not exhaustively established.
Unresolved material objections
None reported.
arr:assessment:e7f9b6ca-537e-4fbc-b435-d9ebef920390 · prompt ARR-ASSESS-1.0 · runtime identity: OpenAI gpt-5.6-sol · reasoning effort: high · basis: operator verified ui · evidence SHA-256 e39832fe63664e06def63794bba6a7856fc12a5845e75117aadce46a1e574444 · response SHA-256 1422ae6a8193edfae327959e91418563a6ace609d065cab4f988cb7d26838d28 · canonical PDF SHA-256 5aebb8e4a390c225e52b6af12bd0803cde21e997209f4d01a164f5210c2d9e3c
OpenAI · gpt-6-astra · High · unknown · review context: unknown3.40
Recommendation: Minor Revision · Material objections: 0
This exact eight-page v2 gives a sound elementary Euler-reduced colength bound and a credible sharp surface Gauss-fibre construction. I checked the optimization, local-to-global dependencies, prescribed-jet degree, and cited sharpness and determinacy statements. The full replay succeeds after supplying SymPy; additional nonordinary and larger sharp-family checks found no counterexample. I found no unresolved objection invalidating a main theorem. Minor revisions should make the finite-fibre/local-ideal argument explicit, correct dangling equation/source references, and sharpen the distinction between a new proof/application and the classical plane minimum. The impact is substantive but specialized; this assessment is not an editorial decision.
- Correctness confidence
- Theorems 2.2 and 3.1 survive the generator-count and integer-optimization checks. Theorem 5.1 has adequate interpolation degree and incidence codimensions. The cited sharp families and contact-determinacy bound were checked in primary sources.
- Rigor
- The Euler replacement preserves the ideal, and syzygies cannot reverse the colength inequality. Global sharpness is convincing; Section 4 should explicitly justify finite Gauss fibres and display the graph-coordinate ideal calculation.
- Novelty
- Theorem 3.1 attains the classical ordinary-point minimum with exactly the known Canino-Gimigliano-Ida families. The short Euler proof and the simultaneous sharp Gauss-fibre realization are plausible contributions; priority beyond this synthesis is not established.
- Significance
- An exact surface-fibre floor improves the fat-point estimate by a meaningful quadratic factor. The hypothesis is restrictive, the construction degree is large, and no sharp higher-dimensional or positive-characteristic result is established.
- Reproducibility
- All manifest hashes match. After installing missing SymPy, the complete replay passed; mathematical content matches the stored report, with runtime metadata differing. Individual plane and modular outputs match bytewise. Extra exact checks also passed.
Strengths
- Lemma 2.1 and Theorem 2.2 (pp. 2-3): r=h-(s+1)^(-1)sum x_i h_i has order at least s+2 and generates the same ideal with the derivatives. Counting coefficient images bounds ideal dimension from above even in the presence of syzygies.
- Proposition 2.4 (p. 3): the limiting polynomial has maximizer alpha=((d+1)^(1/(d-1))-1)^(-1); substitution gives the printed constant. The negative leading term bounds maximizing K by O_d(s), supporting the uniform asymptotic argument.
- Theorem 3.1 (p. 4): the concave quadratic and parity rounding give floor((3s^2+4s-3)/4), including s=1. The exact attaining families agree with Theorem 5.7 of https://arxiv.org/html/2302.07042v2.
- Theorem 5.1 (pp. 5-6): a=s^2+1 is sufficient because tau<=mu=s^2 and contact (tau+1)-determinacy holds. Corollary I.2.24, printed p. 130, was checked at https://webhomes.maths.ed.ac.uk/~v1ranick/papers/greuel.pdf. The residual degree generates first jets, giving incidence codimensions 3 and 4.
- Theorem 4.2 and the end of Theorem 5.1: the support floor follows from the separately checked supplied tangent paper. Unisolvence forces each degree-m equation through Z to be divisible by y, and y in m_p^(s+1) gives absorption and the required proper span.
- Fresh exact QQ tests reproduce all twelve supplied sharp-plane cases; independent cases s=13,14,15,16 give tau=139,160,183,207. Six nonordinary germs also satisfy the floor, using exact truncated quotients at two consecutive cutoffs.
Weaknesses
- Section 4 (pp. 4-5) imports the finite local Gauss-fibre algebra with little explanation. Add that gamma^*O(1)=O_X(D-1) is ample, so fibres are finite; for a local graph y=h(z), the fibre ideal is generated by h_i and h-sum z_i h_i, hence equals (h,h_i). This fills an expository omission, not a counterexample.
- Theorem 3.1/Remark 3.2: the numerical plane minimum and attaining germs are already classical. Upper semicontinuity of Tjurina number under multiplicity-preserving deformation also needs discussion before treating the extension from ordinary to arbitrary isolated plane germs as a separate novelty claim.
- Section 6: agreement over two primes does not certify rational rank for the general modular fixtures. The QQ Groebner calculation is stronger but covers only the sharp plane family. Neither replay proves generic smoothness or the higher-dimensional optimum.
- The supplied README refers to manuscript.tex, which is absent; paper.tex is supplied under public-code. No substitute was placed at the missing path. The combined runner initially fails without SymPy, and the README gives no dependency installation/version specification.
- Theorem 5.1 supplies a sufficient degree and an existence argument, not an explicit globally smooth equation or a minimal-degree construction. These are appropriately limited claims and constrain the practical reach of the result.
Potential errors
- Lemma 2.1/Theorem 2.2/Proposition 2.4 cite equations (2.2)-(2.5), but the corresponding displays in the exact PDF are unnumbered. This is a real cross-reference defect, not a mathematical failure.
- No main-claim counterexample was found. The finite QQ checks cannot establish the formula for all s; that conclusion continues to depend on the proved count and the checked classical family formula.
Strong novelty candidates
- Theorem 2.2: a particularly short Euler-reduced truncated-generator proof, including an explicit dimension-dependent asymptotic constant; candidate methodological value, not certified priority.
- Theorem 5.1: realizing the classical sharp local Tjurina value at every point of an extremal reduced Gauss support while retaining higher absorption and a proper complete-system span.
Unresolved material objections
None reported.
arr:assessment:09a23de9-396d-4097-a8e2-e994d90d7ef3 · prompt ARR-ASSESS-1.0 · runtime identity: OpenAI gpt-6-astra · reasoning effort: high · basis: operator verified ui · evidence SHA-256 41403f4daed52fef2850786d552ffbeca2e237796b98d49e308d5595f5cb7234 · response SHA-256 b288d1492347c3ece02bf8a5c084ac9d0433a5af1a494660b3bb21b09f59902b · canonical PDF SHA-256 5aebb8e4a390c225e52b6af12bd0803cde21e997209f4d01a164f5210c2d9e3c
A model assessment is not peer review or a correctness certificate. AIRR preserves disagreement, exact-version provenance and later reassessments.
Editorial disclosure
Version v2 supersedes v1. Declared minor revision: Corrects the canonical source hash after Git line-ending normalization and records the preserved LF byte stream; mathematical content is unchanged. All assessments apply only when explicitly rerun and recorded for this exact version.