On relative fields of definition for log pairs, Vojta's height inequalities and asymptotic coordinate size dynamics
Nathan Grieve, Chatchai Noytaptim
TL;DR
This work develops a framework linking relative field of definition, log canonical pairs, and Vojta-type inequalities to study asymptotic coordinate-size dynamics in arithmetic dynamics on projective varieties. It introduces a generalized Vojta conjecture for log canonical pairs over finite field extensions and the notion of $ m F/K$ log resolutions, then derives a main dynamical result: for a surjective self-map $f$ on a variety with canonical singularities and a suitable divisor $D$, the coordinate-size contributions along $D$ become negligible relative to global height along generic orbits when $\alpha_f(x)>1$. The authors extend Matsuzawa (2023) to the setting of big line bundles and canonical singularities, and obtain Zariski-non-density results for forward-orbit integral points, connecting arithmetic dynamics with Diophantine inequalities. This provides a powerful approach to understanding asymptotic coordinate size dynamics and highlights the role of log resolutions and thresholds in dynamical Diophantine problems.
Abstract
We build on the perspective of the works \cite{Grieve:Noytaptim:fwd:orbits}, \cite{Matsuzawa:2023}, \cite{Grieve:qualitative:subspace}, \cite{Grieve:chow:approx}, \cite{Grieve:Divisorial:Instab:Vojta} (and others) and study the dynamical arithmetic complexity of rational points in projective varieties. Our main results make progress towards the attractive problem of asymptotic complexity of coordinate size dynamics in the sense formulated by Matsuzawa, in \cite[Question 1.1.2]{Matsuzawa:2023}, and building on earlier work of Silverman \cite{Silverman:1993}. A key tool to our approach here is a novel formulation of conjectural Vojta type inequalities for log canonical pairs and with respect to finite extensions of number fields. Among other features, these conjectured Diophantine arithmetic height inequalities raise the question of existence of log resolutions with respect to finite extensions of number fields which is another novel concept which we formulate in precise terms here and also which is of an independent interest.
