arXiv:1309.7826v1
Abstract
We obtain some new inequalities between the ordinary and the uniform Diophantine exponents for simultaneous Diophantine approximation to four real numbers.
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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.
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Detailed mathematical audit
01Statements3 reported findingsContains unsupported statements
The index-one bound is supported. Every index-two or index-three branch depends on a cone lemma whose required normalization or decisive computation is absent, so those branches could not be independently verified from the supplied details.
The case of index one is verified
Sections 2 and 4 · Theorem 1(1) and case · arXiv:1309.7826v1
The nonzero five-by-five determinant gives the growth alternative (11). Substituting the uniform approximation bounds and balancing its two possible dominant terms gives the polynomial defining , hence .
The branch is not established by Lemma 1 as written
Section 5 · system (17), Lemma 1, and the first part of (9) · arXiv:1309.7826v1
The paper displays the fifteen-variable system and its facet matrix, but it does not supply the ray calculation that would yield . More basically, Lemma 1 allows , which satisfies its homogeneous hypotheses for every although the asserted conclusion fails when . The later logarithmic vector also has and is never shown to lie in the stated subspace . A nonzero normalization and a corrected cone argument may repair the branch, but neither is written or independently verified here.
The high branch and index-three bound are not fully demonstrated
Sections 6-7 · Lemmas 2-3 and the second part of (9) and (10) · arXiv:1309.7826v1
The paper explicitly calls these arguments sketches. Lemma 2 is said to have a similar proof without the required cone calculation, and Lemma 3 is followed only by the instruction to consider a nineteen-dimensional cone. Those omitted computations are precisely what must exclude all other vertices and establish the displayed roots and .
02Proofs4 reported findingsContains unverified proofs
The determinant proof of the index-one regime is complete. All index-two and index-three regimes rely on cone arguments whose normalization or decisive extremal-ray computations are absent. Several branch labels contain uniquely repairable typographical slips.
The index-one growth dichotomy is complete
Section 4 · equations (11)-(16) · arXiv:1309.7826v1
Linear independence makes the integral determinant nonzero. Expanding in approximation errors supplies (12); the two assumed upper growth bounds then contradict it unless at least one adjacent denominator grows with the exponent dictated by .
The normalized-cone implication is incomplete as stated
Section 5 · Lemma 1, system (17), matrix , and equations (18)-(19) · arXiv:1309.7826v1
Invertibility of the displayed facet matrix can show that the chosen homogeneous cone is simplicial, but it does not by itself prove the claimed intersection threshold. The zero vector is a formal counterexample to Lemma 1 as stated, and the proof neither imposes a nonzero normalization nor lists the extremal rays or an equivalent dual certificate. Its application also does not justify replacing by zero.
The decisive cone analyses are omitted
Sections 6-7 · Lemmas 2-3 · arXiv:1309.7826v1
No vertices, inverse matrix, or dual certificate are supplied for either altered inequality system. Because a changed active inequality can create new extremal rays, similarity to Lemma 1 does not formally imply the two stated polynomial thresholds.
Local branch labels and symbols are typographical slips
Sections 2 and 5-7 · index discussion, proof of Lemma 1, branch conclusions, and system (22) · arXiv:1309.7826v1
The index discussion repeats where the fourth component must be . The proof of Lemma 1 refers to (23) where it must refer to its conclusion (19). In the low branch, must be , must be , and the concluding exponent must be rather than . The high-branch sketch must invoke Lemma 2 rather than Lemma 1. Finally, system (22) is missing the comparison sign between and . Each correction is forced by the branch definitions and the surrounding parallel systems.
03Novelty0 reported findingsNo non-novelty findings
No non-novelty findings.