Special Session 105: Dynamics of Many-Particle Systems and Mean-field Equations

Propagation of chaos for multi-species moderately interacting particle systems up to Newtonian singularity
Shuchen Guo
University of Oxford
England
Co-Author(s):    Jose Carrillo and Alexandra Holzinger
Abstract:
We derive a class of multi-species aggregation-diffusion systems from stochastic interacting particle systems via relative entropy method with quantitative bounds. We show an algebraic L^1-convergence result using moderately interacting particle systems approximating attractive/repulsive singular potentials up to Newtonian/Coulomb singularities without additional cut-off on the particle level. The first step is to make use of the relative entropy between the joint distribution of the particle system and an approximated limiting aggregation-diffusion system. A crucial argument in the proof is to show convergence in probability by a stopping time argument. The second step is to obtain a quantitative convergence rate to the limiting aggregation-diffusion system from the approximated PDE system. This is shown by evaluating a combination of relative entropy and L^2-distance.