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2409.13662

Hölder curves with exotic tangent spaces

Eve Shaw, Vyron Vellis

correctmedium confidence
Category
Not specified
Journal tier
Strong Field
Processed
Sep 28, 2025, 12:56 AM

Audit review

The uploaded paper (Shaw–Vellis) proves exactly the target statement (Theorem 1.2) using a two-model planar construction for discrete exponents α_n = log(5n−6)/log n, a measure-theoretic choice-function argument to ensure “randomness,” explicit control of tangents at typical points (with precise cut-point counts), and then a snowflaking + Assouad embedding step to reach every s>1; see the statement of Theorem 1.2 and the proof outline in Sections 1.2, 5–9 . Tangents are defined via Attouch–Wets convergence (following [BL15]) , and the bi-Hölder invariance of tangents needed for the snowflake/embedding step is provided in Section 9 (Lemma 9.1) . The candidate solution adopts the same two-step strategy and is substantively correct; it differs only in a minor quantitative detail: it incorrectly states the exact count of local cut points in the discrete-stage tangents as (n^k−1)/(n−1), whereas the paper proves 1/(5n−7)((5n−6)^k−1) (Proposition 8.1, used in the proof of Theorem 1.2) . This discrepancy does not affect the main conclusion (infinitely many pairwise non-homeomorphic tangents), so the model’s approach aligns with the paper’s proof.

Referee report (LaTeX)

\textbf{Recommendation:} minor revisions

\textbf{Journal Tier:} strong field

\textbf{Justification:}

The paper delivers a clear and convincing construction demonstrating that typical tangents of Hölder curves can be arbitrarily complex, in stark contrast with the Lipschitz case. The technical development (random choice functions, parameterization, Ahlfors regularity, and tangent extraction) is well organized, and the snowflaking+Assouad transfer is executed carefully. Minor refinements to presentation would further enhance readability, but the mathematical content appears sound and significant.