2410.17944
Regularity of non-autonomous self-similar sets
Antti Käenmäki, Alex Rutar
correctmedium confidence
- Category
- math.DS
- Journal tier
- Top Field-Leading
- Processed
- Sep 28, 2025, 12:56 AM
- arXiv Links
- Abstract ↗PDF ↗
Audit review
The paper proves that for non-autonomous self-similar IFSs satisfying the bounded neighbourhood condition (BNC), the Assouad dimension equals several limit forms built from the unique zeros θ(n,m) of block pressure functions ϕn,m, see Theorem A and Theorem 4.3 (dim_A K = lim_m sup_n θ(n,m) = lim_m limsup_n θ(n,m) = inf_m limsup_n θ(n,m)) under BNC . The candidate solution establishes the same formula via a block-pressure P(t) := lim_m sup_n ϕn,m(t) and a covering argument that uses BNC directly. The model’s subadditivity/weighted-counting proof is sound and aligns with the paper’s setting and assumptions (BNC, definitions of T(r), π, and ϕn,m) . While the paper proceeds via bi-Lipschitz decomposability and a disc-packing characterization of Assouad dimension , the model’s approach is a valid alternative. Minor nit: the model asserts P(t) is strictly decreasing and continuous; monotonicity suffices and strictness/continuity need not be invoked. Overall, both reach the same result; the proofs are different but compatible.
Referee report (LaTeX)
\textbf{Recommendation:} no revision \textbf{Journal Tier:} top field-leading \textbf{Justification:} The paper provides a sharp, conceptually cohesive characterization of Assouad dimension for non-autonomous self-similar sets under BNC. Its reduction to symbolic space, submaximality framework, and careful treatment of regularity and examples consolidate and extend prior results. The arguments appear correct and well-explained, and the examples compellingly exhibit necessity and limitations of assumptions.