Counting the number of $m$-periodic $\mathcal{O}_{K}$-points of a discrete dynamical system with applications from arithmetic statistics, V
Brian Kintu
TL;DR
This work analyzes $m$-periodic points of polynomial maps $\varphi_{d,c}(z)=z^{d}+c$ over rings of integers $\mathcal{O}_{K}$ modulo inert primes, connecting explicit counts, densities, and averages to arithmetic statistics. It establishes precise dichotomies for counts $N_{c}^{(m)}(p)$ and $M_{c}^{(m)}(p)$ in families $\varphi_{p^{\ell},c}$ and $\varphi_{(p-1)^{\ell},c}$ under inert primes, then derives asymptotic densities, average behaviors, and zero/constant Artin-Mazur zeta functions for these reductions. The paper extends the analysis to the associated monogenic number fields $\mathbb{Q}_{f}$ and $\mathbb{Q}_{g}$, giving bounds on the number of fields with bounded discriminant, proving existence of fields with prescribed Galois groups and class numbers, and establishing Sato-Tate equidistribution for families of Artin $L$-functions. Overall, it creates a bridge between discrete dynamical systems over number fields and arithmetic-statistical phenomena, highlighting how dynamical counts translate into field-counting, zeta, and L-function behavior with broad implications for equidistribution and monogenicity in number theory.
Abstract
In this follow-up paper, we again inspect a surprising relationship between the set of $m$-periodic points of a polynomial map $\varphi_{d, c}$ defined by $\varphi_{d, c}(z) = z^d + c$ for all $c, z \in \mathcal{O}_{K}$ and the coefficient $c$, where $K$ is any number field of degree $n\geq 2$, $d>2$ is an integer and $m\in \mathbb{Z}_{\geq 2}$ is any fixed (period). As before, we again study counting problems which are inspired by advances on $m$-torsion point-counting in arithmetic statistics and $m$-periodic point-counting in arithmetic dynamics. In doing so, we then first prove that for any prime $p\geq 3$ and for any fixed $\ell\in \mathbb{Z}_{ \geq 1}$ and (period) $m\in \mathbb{Z}_{\geq 2}$, the average number of distinct $m$-periodic integral points of any $\varphi_{p^{\ell}, c}$ modulo prime ideal $p\mathcal{O}_{K}$ is unbounded or zero as $c$ tends to infinity. Motivated further by $K$-rational periodic point-counting work of Benedetto along with conjectural work of Hutz on $m$-periodic points of any $\varphi_{(p-1)^{\ell}, c}$ for any prime $p\geq 5$ and any fixed $\ell \in \mathbb{Z}_{\geq 1}$ in arithmetic dynamics, we then also prove that for any fixed (period) $m\in \mathbb{Z}_{\geq 2}$, the average number of distinct $m$-periodic integral points of any $\varphi_{(p-1)^{\ell}, c}$ modulo prime $p\mathcal{O}_{K}$ is $1$ or $2$ or $0$ as $c\to \infty$. Finally, we then apply here density, polynomial-counting, field-counting, and Sato-Tate equidistribution results from arithmetic statistics, and thereby obtaining further counting and statistical results on the irreducible monic polynomials, Artin-Mazur zeta functions, algebraic number fields, and lastly on Artin $L$-functions arising naturally in our polynomial discrete dynamical settings.
