English

$p$-Adic interpolation of orbits under rational maps

Number Theory 2022-02-04 v1 Dynamical Systems

Abstract

Let LL be a field of characteristic zero, let h:P1P1h:\mathbb{P}^1\to \mathbb{P}^1 be a rational map defined over LL, and let cP1(L)c\in \mathbb{P}^1(L). We show that there exists a finitely generated subfield KK of LL over which both cc and hh are defined along with an infinite set of inequivalent non-archimedean completions KpK_{\mathfrak{p}} for which there exists a positive integer a=a(p)a=a(\mathfrak{p}) with the property that for i{0,,a1}i\in \{0,\ldots ,a-1\} there exists a power series gi(t)Kp[[t]]g_i(t)\in K_{\mathfrak{p}}[[t]] that converges on the closed unit disc of KpK_{\mathfrak{p}} such that han+i(c)=gi(n)h^{an+i}(c)=g_i(n) for all sufficiently large nn. As a consequence we show that the dynamical Mordell-Lang conjecture holds for split self-maps (h,g)(h,g) of P1×X\mathbb{P}^1 \times X with gg \'etale.

Keywords

Cite

@article{arxiv.2202.01673,
  title  = {$p$-Adic interpolation of orbits under rational maps},
  author = {Jason P. Bell and Xiao Zhong},
  journal= {arXiv preprint arXiv:2202.01673},
  year   = {2022}
}

Comments

12 pages

R2 v1 2026-06-24T09:18:11.271Z