Published online by Cambridge University Press: 23 February 2021
We prove a quantitative partial result in support of the dynamical Mordell–Lang conjecture (also known as the DML conjecture) in positive characteristic. More precisely, we show the following: given a field K of characteristic p, a semiabelian variety X defined over a finite subfield of K and endowed with a regular self-map
$\Phi :X{\longrightarrow } X$
defined over K, a point
$\alpha \in X(K)$
and a subvariety
$V\subseteq X$
, then the set of all nonnegative integers n such that
$\Phi ^n(\alpha )\in V(K)$
is a union of finitely many arithmetic progressions along with a subset S with the property that there exists a positive real number A (depending only on X,
$\Phi $
,
$\alpha $
and V) such that for each positive integer M,
D. Ghioca and S. Saleh were partially supported by a Discovery Grant from NSERC, A. Ostafe by ARC Grants DP180100201 and DP200100355, and I. Shparlinski by ARC Grant DP200100355.