2104.11634
Equilibrium States for the Random β-Transformation through g-Measures
Karma Dajani, Kieran Power
correctmedium confidence
- Category
- Not specified
- Journal tier
- Specialist/Solid
- Processed
- Sep 28, 2025, 12:56 AM
- arXiv Links
- Abstract ↗PDF ↗
Audit review
The candidate solution reproduces the paper’s construction and arguments: it builds the Markov partition and mixing SFT (Y,σ) for β∈B, defines the summable-variation potentials ϕ_{θ,α}, computes the explicit eigenfunction H_{θ,α} and the resulting g-function g_{θ,α}(y)=e^{θ(e0(y))}/∑_i e^{θ(i)}, shows µ(Y′)=1 and pushes forward to Kβ-invariant measures, and establishes non-productness for infinitely many θ. These steps match the paper’s proofs (Definition of B and coding; Lemma 4.2; Proposition 4.5; g-function identity; Theorem 5.1; Section 5.1) . Two minor discrepancies: (i) the paper states g_{θ,α}=g_{θ′,α′} iff θ=θ′, whereas equality holds modulo an additive constant to θ (the candidate notes this normalization-invariance); (ii) in part (d) the candidate invokes an unjustified shortcut for the 1/β relation that the paper derives rigorously via the Markov model. With that fix, the proofs coincide.
Referee report (LaTeX)
\textbf{Recommendation:} minor revisions
\textbf{Journal Tier:} specialist/solid
\textbf{Justification:}
The submission gives an explicit, well-structured family of equilibrium/g-measures for the random β-transformation for a class of parameters β where a Markov coding exists. The eigenfunction calculation is transparent and the translation to Kβ-invariant measures is handled carefully. The novelty over previously known product measures is cleanly established via a comparison of g-functions/Markov models. Small clarifications (parameter normalization; a brief reminder of the Markov computation in the novelty section) would improve readability.