2407.19091
LI-YORKE CHAOTIC WEIGHTED COMPOSITION OPERATORS
Nilson C. Bernardes Jr., Fernanda M. Vasconcellos
correctmedium confidence
- Category
- Not specified
- Journal tier
- Strong Field
- Processed
- Sep 28, 2025, 12:56 AM
- arXiv Links
- Abstract ↗PDF ↗
Audit review
The paper’s Theorem 1 gives a necessary-and-sufficient criterion for Li–Yorke chaos of weighted composition operators C_{w,f} on C0(X) in terms of a sequence of relatively compact open sets (Bi) and conditions (A)–(B), and proves both directions using a residual-set argument and Banach–Steinhaus; it also extracts (A) from an irregular vector constructed via Bi := {x: |ψ(x)| > i^{-1}} and derives (B) by contradiction if sup_{i,n}‖w(n)‖_{f^{-n}(Bi)} were finite. This exactly matches the statement the model addresses, and the paper’s proof is sound (see Theorem 1 and its proof, including the Urysohn-lemma step and the residual/Banach–Steinhaus argument ). The model’s solution proves the same equivalence: the “only if” direction coincides with the paper’s reasoning, while the “if” direction constructs an explicit irregular vector using bump functions and a diagonal smallness subsequence, rather than appealing to Banach–Steinhaus. There is a minor technical nit: the model writes an equality (⋆) that should be an inequality (it does not affect the argument), and its convenience assumption of pairwise disjoint supports can be implemented by a mild refinement (or avoided entirely by following the paper’s residual approach). Overall, both are correct; the proofs differ in technique.
Referee report (LaTeX)
\textbf{Recommendation:} minor revisions \textbf{Journal Tier:} strong field \textbf{Justification:} The manuscript delivers complete characterizations of Li–Yorke chaos for weighted composition operators on C0(X) and Lp(μ), with clear proofs grounded in standard tools from linear dynamics and functional analysis. The results are of independent interest and yield clean criteria for weighted shifts, complementing and extending prior work. Minor enhancements (explicit references for bump functions in LCH spaces, a brief reminder of Banach–Steinhaus usage, and notational streamlining) would further increase accessibility, but the core contributions and correctness are solid.