arXiv:2607.27780v1

On a question of Gowers related to Littlewood's conjecture

Frederik Broucke, Máté Matolcsi, Szilárd Gy. Révész

math.NT11J1343A35

Abstract

In a blogpost in 2009, Gowers raised a possible approach to Littlewood's conjecture in Diophantine approximation, leading to a question about the existence of sufficiently many points in the unit cube such that "hyperbolic distance" between any two of them is large. In this note we answer this question by an explicit construction. This shows that this approach to prove Littlewood's conjecture cannot work, unless some further refinements are added.

AI-generated audit

Audit summary

Audited against arXiv v1

Not a correctness certificate. A “Correct” result may include yellow typos or minor formal corrections that do not affect substantive soundness. It means this audit found no unresolved substantive error under the stated criteria; it does not replace expert scrutiny or formal verification.

Current report

Detailed mathematical audit

Generated August 15, 2026
01Statements3 reported findingsCorrect

The central lattice theorem, its finite-point consequence, and the Delsarte bounds are correct. The exact-nn conclusion follows immediately from the lattice-point asymptotic by taking a subset and absorbing finitely many small cases, so the mandatory finding gate records no gap there.

Theorem 2Correct

Existence of a product-admissible full-rank lattice

Pages 1–2 · Theorem 2 · arXiv:2607.27780v1

For a totally real number field KK of degree dd, the Minkowski image of OK\mathcal O_K is a full-rank lattice in Rd\mathbb R^d. For every nonzero αOK\alpha\in\mathcal O_K, the coordinate product is NK/Q(α)|N_{K/\mathbb Q}(\alpha)|, a nonzero integer, and is therefore at least 11. Hence the lattice meets Hd={x:x1xd<1}H^d=\{x:|x_1\cdots x_d|<1\} only at the origin.

Main applicationCorrect

Affirmative answer to Gowers's finite-point question

Page 2 · Paragraph following Remark 3 · arXiv:2607.27780v1

The number of lattice points in the growing cube is asymptotic to R/vol(Rd/Λ)R/\operatorname{vol}(\mathbb R^d/\Lambda), while distinct scaled points have coordinate-product separation at least 1/R1/R. For any fixed c<vol(Rd/Λ)1c<\operatorname{vol}(\mathbb R^d/\Lambda)^{-1}, selecting nn points once the count exceeds nn, and decreasing cc to cover the finitely many smaller values of nn, gives the claimed c/nc/n separation for every positive integer nn.

Section 3Correct

Delsarte quantities and asymptotic bounds

Pages 3–4 · Section 3 · arXiv:2607.27780v1

The autocorrelation measure of a separated point set has the stated support, atom, mass, and nonnegative Fourier coefficients. The test function φ=ε1χχ\varphi=\varepsilon^{-1}\chi*\chi is positive definite, is nonpositive outside HεdH_\varepsilon^d because it vanishes there, and has integral ε\varepsilon. These facts, together with the applicable strong-duality theorem, give the displayed bounds and Nd(ε)ε1N_d(\varepsilon)\asymp\varepsilon^{-1}.

Strong duality source, Theorem 5.6
02Proofs4 reported findingsCorrect

All substantive proof steps and material cited inputs are correct and complete after immediate-consequence closure. Three literal notation defects have unique, verified repairs and remain visible in yellow without lowering the proof status.

Littlewood lower boundTypo

An extra closing parenthesis should be removed

Page 1 · Paragraph immediately after the display defining XnX_n · arXiv:2607.27780v1

The factor is printed as (lk))α\lVert(l-k))\alpha\rVert. Remove the extra closing parenthesis to obtain (lk)α\lVert(l-k)\alpha\rVert. The correction is uniquely mechanical and changes no inequality or argument.

Footnote 1Typo

The cyclotomic subgroup generator has the wrong exponent

Page 2 · Footnote 1 to the proof of Theorem 2 · arXiv:2607.27780v1

The printed automorphism ζpζpd\zeta_p\mapsto\zeta_p^d need not generate a subgroup of order (p1)/d(p-1)/d; for d=2d=2 and p=5p=5, exponent 22 generates the whole Galois group. If gg is a primitive root modulo pp, replace the subgroup by H=ζpζpgdH=\langle\zeta_p\mapsto\zeta_p^{g^d}\rangle, equivalently the unique subgroup of order (p1)/d(p-1)/d. Its fixed field has degree dd, and it is totally real because (p1)/d(p-1)/d is even, so HH contains complex conjugation. The required subgroup order and index uniquely determine this verified mechanical repair; the norm proof is unchanged.

Scaling displayTypo

The strict inequality should be non-strict

Page 2 · Display immediately after the asymptotic for #YR\#Y_R · arXiv:2607.27780v1

The display prints i=1d(λiλi)/R1/d>1/R\left|\prod_{i=1}^d(\lambda_i-\lambda_i')/R^{1/d}\right|>1/R. Replace >> by \geq. Theorem 2 gives i(λiλi)1\left|\prod_i(\lambda_i-\lambda_i')\right|\geq1, with equality possible, and this non-strict bound is exactly what the application requires.

Section 3Correct and complete

Convolution and strong-duality argument

Pages 3–4 · Section 3 · arXiv:2607.27780v1

The Fourier-positivity, support, normalization, and mass calculations are correct with the stated Haar normalization. The cited strong-duality result applies to this compact Abelian-group setting, and the paper also gives a valid direct proof of the upper bound D(Hεd)1/εD'(H_\varepsilon^d)\leq1/\varepsilon.

Strong duality source, Theorem 5.6 and Remark 5.4
03Novelty1 reported findingContains non-new main statements

The central admissible-lattice theorem and the resulting finite-point construction follow directly from a publicly available 2018 Frolov-lattice construction.

Theorem 2 and main applicationPreviously established

The admissible lattice and resulting point construction were already available

Theorem 2 on pages 1–2 and its consequence for Problem 1 on page 2 · arXiv:2607.27780v1

Kacwin, Oettershagen, Mario Ullrich, and Tino Ullrich, public on February 23, 2018, define an admissible lattice by infk0i(Vk)i>0\inf_{k\neq0}|\prod_i(Vk)_i|>0. Their Proposition 2.2 and Equations (1.5)–(1.6) construct, in every dimension, a Vandermonde lattice with minimum product 11. Thus every nonzero λVZd\lambda\in V\mathbb Z^d satisfies iλi1|\prod_i\lambda_i|\geq1, exactly the condition ΛHd={0}\Lambda\cap H^d=\{0\} in Theorem 2. Their scaling and lattice-point formulas, Equations (1.3)–(1.4), then immediately yield point sets in the unit cube with cardinality proportional to the scale and product separation proportional to its reciprocal; selecting exactly nn points gives the stated answer to Gowers's question.

Kacwin–Oettershagen–Ullrich–Ullrich, Definition 2.1 and Proposition 2.2
Detailed audit reportFull reasoning, manuscript locations, and references.
Open report PDF ↗

Author response

Challenge an audit finding

Local workflow preview

A listed author may submit formal evidence that an audit is inaccurate. The response would be considered in a fresh AI re-evaluation; it would not edit the audit automatically.

Paper
arXiv:2607.27780v1
Authors listed
Frederik Broucke, Máté Matolcsi, Szilárd Gy. Révész
Audit date
August 15, 2026
  1. 01Establish identityMatch an authenticated scholarly identity to this paper.
  2. 02Submit evidenceIdentify the finding and give a formal mathematical response.
  3. 03Re-evaluateA separate agent checks the response and records a disposition.
Recommended production method

Authenticate with ORCID, then require an exact arXiv match

MathAudit should accept the identity only when ORCID OAuth authenticates the claimant's iD and this exact arXiv paper appears in arXiv's public authority feed for that iD. A matching name alone is not sufficient.

ORCID OAuth and arXiv authority-record lookup are not connected in this local prototype.

Email fallback for papers without a linked ORCID

A production fallback could send a one-time link only when the submitted address matches an independently maintained author-contact allowlist for this paper. MathAudit must return the same message for every address so the form cannot reveal which contacts are on that list.

This demonstration does not send, store, or compare the address.

Structured response preview

This form remains unavailable until production identity verification succeeds. Nothing entered here is submitted.

This panel never establishes authorship in the local prototype. A production result should be described narrowly as an authenticated ORCID match or control of a separately allowlisted author-contact mailbox.