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2012.11598

Cohomology groups, continuous full groups and continuous orbit equivalence of topological Markov shifts

Kengo Matsumoto

correctmedium confidence
Category
Not specified
Journal tier
Specialist/Solid
Processed
Sep 28, 2025, 12:55 AM

Audit review

The paper proves that Γ-strong continuous orbit equivalence is equivalent to eventual conjugacy for irreducible, non-permutation 0–1 matrices (Theorem 6.6), via an explicit construction: starting from Γ-scoe, it produces τ2 = h ◦ τ1^{-1} ◦ h^{-1} and postcomposes h by τ2 to obtain a new orbit equivalence whose forward cocycle is identically 1, which then yields eventual conjugacy (Proposition 6.3, Lemma 6.4, Proposition 6.5, Theorem 6.6) . By contrast, the candidate solution precomposes by τ∈Γ_A and asserts a specific transformation law for the forward cocycle that forces it to be 1; this step is incorrect and internally inconsistent (they alternately write c1' = c1∘τ + … and c1' = c1 + … without justification). The correct adjustment, as done in the paper, is to postcompose by τ2 on the B-side, not to precompose on the A-side .

Referee report (LaTeX)

\textbf{Recommendation:} no revision

\textbf{Journal Tier:} specialist/solid

\textbf{Justification:}

The equivalence of Γ-strong continuous orbit equivalence and eventual conjugacy is established clearly and correctly under standard hypotheses. The paper's argument is direct and uses only the machinery already developed in the text. Citations to prior work are appropriate, and the proof in Section 6 stands well on its own.