2102.08316
Typical coexistence of infinitely many strange attractors
Pablo G. Barrientos, Juan Davi Rojas
incompletemedium confidence
- Category
- Not specified
- Journal tier
- Specialist/Solid
- Processed
- Sep 28, 2025, 12:56 AM
- arXiv Links
- Abstract ↗PDF ↗
Audit review
The paper states and proves Theorem A: in a Cd,r-Berger domain U (m ≥ 3, 3 ≤ d < r − 1), there is a residual set R of k-parameter families for which, for Lebesgue-a.e. parameter, the diffeomorphism has infinitely many non-hyperbolic strange attractors (Theorem A and its reduction to Theorem B) . The proof skeleton is: (i) parameter-dependent renormalization producing Hénon-like families (Definition 2.1, Proposition 2.2, Lemma 2.4, and the rescaling to the parabola family) ; (ii) use of prevalence results for Hénon-like families to get a uniform positive-measure set of good parameters in each window; and (iii) a Borel–Cantelli argument across infinitely many windows to conclude that a.e. parameter falls in infinitely many good windows (the “second Borel–Cantelli Lemma” step) . The candidate solution follows the same blueprint: persistent tangencies in Berger domains, Palis–Takens/Mora–Viana renormalization to small-Jacobian Hénon-like maps, a uniform positive-measure parameter set in each unfolding window, and a Kolmogorov-typicality scheme using a quasi-independence/Borel–Cantelli mechanism. However, both accounts are incomplete on the probabilistic step: the paper invokes the second Borel–Cantelli lemma without establishing independence or a suitable quasi-independence estimate for the parameter events across different windows (the argument extracts disjoint subcollections within each level but does not control cross-level correlations) . The candidate solution mentions quasi-independence but does not supply the needed estimate either. Aside from this gap, the renormalization and prevalence parts match and are consistent with the cited framework (Definition 1.1; Theorem B; Definition 2.1; Lemma 2.4) .
Referee report (LaTeX)
\textbf{Recommendation:} minor revisions
\textbf{Journal Tier:} specialist/solid
\textbf{Justification:}
The manuscript tackles a central question on Kolmogorov-typical coexistence of infinitely many strange attractors within Berger domains. The renormalization framework and the prevalence input are well set up and technically solid. The only substantive issue is the probabilistic step: independence or a quantitative quasi-independence across levels is not established, yet the second Borel–Cantelli lemma is applied to claim full-measure limsup. Providing an explicit quasi-independence lemma (or citing Kochen–Stone/Sprindžuk with verification of hypotheses) would complete the proof. With that fix, the contribution is sound and valuable to specialists in smooth dynamics.