Global classical solutions to the ionic Vlasov-Poisson-Boltzmann system in a 3D periodic box
Fucai Li, Yichun Wang
TL;DR
This work proves the global existence and exponential decay of classical solutions to the ionic Vlasov-Poisson-Boltzmann system in a 3D periodic box for small Maxwellian perturbations. The authors develop a nonlinear $L^2$ energy framework that couples ion kinetics to a nonlinear Poisson-Poincaré equation, and they establish novel elliptic estimates for the PPE along with coercivity results for the linearized collision operator. Key contributions include a robust macro-micro decomposition, PPE-based control of macroscopic quantities, and a bootstrap argument yielding global-in-time stability. This advances the mathematical understanding of ionic plasmas with self-consistent electrostatics and ion-ion collisions, offering a rigorous foundation for kinetic models with nonlinear Poisson-type couplings.
Abstract
We investigate the global well-posedness of the ionic Vlasov-Poisson-Boltzmann system which models the evolution of dilute collisional ions. This system distinguishes the electronic Vlasov-Poisson-Boltzmann system via an additional exponential nonlinearity in the coupled Poisson-Poincaré equation, which introduces essential mathematical difficulties. In a three-dimensional periodic box, We establish the existence of a unique global-in-time classical solution with an exponential decay under small initial perturbations of a global Maxwellian that preserve mass, momentum and energy conservation laws. Our approach combines a nonlinear energy method with quantitative nonlinear elliptic estimates and new coercivity inequalities for the linearized collision operator $\mathcal{L}$ in ion dynamics.
