2104.12877
Variation of the Canonical Height in a Family of Polarized Dynamical Systems
Patrick Ingram
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 proves the asymptotic with power savings: ĥ_{f_t}(P_t) = ĥ_f(P) h_B(t) + O(h_B(t)^{2/3}) in general, and O(h_B(t)^{1/2}) when B is rational, exactly as stated (see the statement and discussion of Theorem 1 and its proof outline, including the optimization over k via d^{3k} ≈ h_B(t) to get 2/3, and the P^1 improvement via d^{2k} ≈ h(t) leading to 1/2) . The method relies on explicit elimination bounds and the curve-height comparison h_{B,D} = h_{B,E} + O(h_{B,E}^{1/2}) for heights of the same degree on a curve, to pass from D(F,P)(t) to ĥ_f(P)h_B(t) with O(h^{1/2}) error on the base . The candidate model gives a different route: it sketches a local-to-global decomposition using adelic local heights and then bounds the resulting truncated proximity/gcd term by subspace-theorem estimates (2/3 on a general curve, 1/2 on P^1). While the model’s outline leaves technical details implicit (notably the precise truncated-proximity theorems invoked and the rigorous construction of the local decomposition and auxiliary functions), its conclusion matches the paper’s theorem and is consistent with known subspace-theoretic bounds. Hence, the two arrive at the same main statement by different methods; the paper’s proof is fully detailed and complete in the uploaded text, and the model’s proof is plausible but would need additional citations and hypotheses to be fully rigorous.
Referee report (LaTeX)
\textbf{Recommendation:} minor revisions
\textbf{Journal Tier:} strong field
\textbf{Justification:}
The work gives sharp power-savings for the variation of canonical heights over curves, with a method that is robust and avoids heavy Diophantine approximation machinery. The results extend and strengthen the foundational asymptotic of Call–Silverman and align with best-known exponents in special cases. The presentation is clear and complete; minor clarifications would further improve readability and reproducibility.