arXiv:2606.08865v1

The Dirichlet spectrum with respect to L1L_1 norm is [12,1]\left[\frac12,1\right]

Nikita Shulga

math.NT11J0611J0411J70

Abstract

We prove that the one-dimensional Dirichlet spectrum with respect to approximation in L1L_1 norm D[1]\mathbb{D}^{[1]} satisfies D[1]=[12,1]. \mathbb{D}^{[1]}=\left[\frac12,1\right]. This is equivalent to the fact that the Minkowski spectrum M\mathbb M, associated with the Minkowski diagonal continued fraction, satisfies M=[14,12]. \mathbb M=\left[\frac14,\frac12\right]. Further, we show that level sets Θm={α(0,1)Q:m(α)=m}, Θ_m=\{α\in(0,1)\setminus\mathbb Q:\mathfrak m(α)=m\}, where m(α)\mathfrak{m}(α) is the Minkowski constant of αα, have Hausdorff dimension strictly greater than 1/21/2 for any m(1/4,1/2]m\in(1/4,1/2], while dimHΘ1/4=12\dim_H Θ_{1/4}=\frac{1}{2}.

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 18, 2026
01Statements3 reported findingsCorrect

The determination of the L1L_1 Dirichlet spectrum as [1/2,1][1/2,1], the corresponding Minkowski spectrum, and the Hausdorff-dimension assertions for the level sets are supported by the continued-fraction construction and its quantitative estimates.

Theorem 1.1Correct

The complete L1L_1 Dirichlet and Minkowski spectra

Pages 2–3 and 12–18 · Theorem 1.1 and Sections 5–6 · arXiv:2606.08865v1

The universal upper and lower bounds follow from the geometry-of-numbers normalization. For every target value, the paper constructs two continued fractions whose interlaced denominator scales control the three possible cut types. The estimates for those cuts show that the limsup constant is the prescribed value, while the central digit prevents an unintended smaller value. The endpoint constructions are included, yielding the closed interval [1/2,1][1/2,1] and, after the stated normalization, [1/4,1/2][1/4,1/2] for the Minkowski spectrum.

Proposition 2.1Correct

Normalization linking the two spectra

Pages 4–5 · Proposition 2.1 · arXiv:2606.08865v1

At a best-approximation denominator QnQ_n, minimizing the L1L_1 length q/t+tqαq/t+t\|q\alpha\| over tt gives the square-root normalization. Passing through the consecutive denominator intervals yields m(α)=(d[1](α))24,m(\alpha)=\frac{(d^{[1]}(\alpha))^2}{4}, so the Minkowski spectrum is exactly one half of the normalized L1L_1 Dirichlet spectrum. The endpoint values in Theorem 1.1 therefore transform consistently.

Theorems 1.3, 7.3 and 7.6Correct

Hausdorff dimensions of the level sets

Pages 3 and 18–23 · Section 7 · arXiv:2606.08865v1

The lower bounds use independent continued-fraction cylinders with bounded distortion and enough free digits, while the upper bounds convert a prescribed Dirichlet value into quantitative restrictions on successive denominator ratios. The covering sums have the stated critical exponents. The exceptional endpoint is handled separately rather than being inferred from a nonuniform interior estimate.

02Proofs2 reported findingsCorrect

The proof of the spectral interval and the dimension calculations are correct and complete. The division into the three possible denominator-cut regimes covers all cases, and the limiting and endpoint arguments use estimates uniform enough for the stated conclusions.

Sections 5–7Correct and complete

Continued-fraction construction and dimension estimates

Pages 12–23 · Sections 5–7 · arXiv:2606.08865v1

The recursive choice of partial quotients preserves the required order of denominator scales. Each possible position of the height parameter is assigned to exactly one of the Type 1, Type 2, or Type 3 estimates, so no transition regime is omitted. The cylinder lengths and branching counts used in the mass-distribution argument agree with the continued-fraction distortion bounds, and the complementary cover yields the matching upper estimate.

Theorems 7.3 and 7.6Correct and complete

Interior upper bound and endpoint dimension

Pages 19–22 · Section 7.2 · arXiv:2606.08865v1

For an interior level, infinitely many occurrences of the word (L,2,L)(L,2,L) would force a cut value above the prescribed parameter, so the level set lies in a continued-fraction subshift omitting that word and has dimension below one. At the lower endpoint, numbers with partial quotients tending to infinity give the lower bound 1/21/2, while the covering by cylinders with uniformly large eventual digits gives the matching upper bound.

03Novelty0 reported findingsNo non-novelty findings

No non-novelty findings.

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:2606.08865v1
Authors listed
Nikita Shulga
Audit date
August 18, 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.