OpenAI claim summary for Math-2688
mathematicsTop Open Problemscontributionliterature_reportClaim: literature report
Summary of a claim published in openai/math; not a claim by this platform.
The attractor corollary asserts $\dim_HK=\min(1,s_*)$ for arbitrary signed real contracting similarities with no exact overlaps, without separation or arithmetic assumptions. Its definition and all-word equivalence cover the recorded absence of collisions between distinct nonempty words. Repeated generators would be exact overlaps and are excluded from this corollary. The manuscript's broader measure theorem allows collisions, but that extra scope is not needed for the attractor assertion.
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Manuscript
Contents
Dimension of a real self-similar attractor without exact overlaps
OpenAI's claim
For any finite real self-similar probability measure, its dimension is claimed to equal the smaller of one and map-walk entropy rate divided by Lyapunov exponent, even with exact overlaps and signed unequal contractions. The cited manuscript argues for that result; its relation to this problem is specified below.Mathematical statement of the claimed result
Mathematical claim 1.
Consider a nonempty finite indexed family $\Phi=(\varphi_i)$ consisting of similarities $\varphi_i(x)=r_ix+t_i$ of the real line, with arbitrary translations and $0<|r_i|<1$, and positive probability vector $p$. Let $\mu$ be its self-similar measure, $\chi=\sum_i p_i\log(1/|r_i|)$, and $h_{\mathrm{RW}}=\lim_{n\to\infty}H(G_n)/n$, where $G_n$ is the random complete affine composition of $n$ independent $p$-distributed generators. OpenAI claims \[ \dim_H\mu=\min\{1,h_{\mathrm{RW}}/\chi\}. \] No separation is imposed; repeated generators and exact overlaps are allowed. The attractor corollary assumes absence of exact overlaps (distinct finite words give distinct complete maps) and claims $\dim_HK_\Phi=\min\{1,s_*\}$, with $\sum_i|r_i|^{s_*}=1$. The measure assertion is stronger than that no-overlap set corollary.Outline of the argument
Manuscript 1 (family 148, 2026-09-24): Finite-law comparisons expose entropy hidden within grid cells as fair two-point information at finer scales. Blocking and conditioning on symbol counts fixes the composed contractions while preserving map entropy; a hypothetical dimension loss would create too much fair-pair mass in a fine-scale band, contradicting the entropy estimates.Formal verification
For family 148, the scope page documents the following selections. The selected dimension identity permits signed unequal contractions and exact coincidences. Further declarations treat homogeneous measures and overlap-free attractors; density and absolute continuity are not selected. The documented statement covers the main claim of manuscript 1. Comparator files: SelfSimilar.lean, SelfSimilarCorollaries.lean. Declarations: OAI.EntropyRateDimension.entropy_rate_dimension, OAI.EntropyRateDimension.Extensions.homogeneous_dimension_direct, OAI.CorSetReference.cor_set.This site has not executed the Lean files or checked their dependencies. These descriptions report the scope of the linked declarations, rather than a new verification of the proofs.
Status caveat
OpenAI attributes these results to an internal model. Its release notice cautions that results lacking full formalization can contain mistakes. This site has not independently assessed the proofs; a solved label records the scope of the reported claim.Sources
- OpenAI, The entropy-rate dimension formula for self-similar measures on the line, 2026-09-24; citation key
OAI:The-entropy-rate-dimension-formula-for-self-similar-measures-on-the-line-September-24-2026. PDF (GitHub); PDF (direct); Manuscript page and citation; Latest version; Statement source: cor:set; Statement source: thm:main. - Family 148: Lean scope.
- Comparator SelfSimilar.json.
- Comparator SelfSimilar.lean.
- Comparator SelfSimilarCorollaries.json.
- Comparator SelfSimilarCorollaries.lean.
- OpenAI catalogue entry.