English

A cross-diffusion system derived from a Fokker-Planck equation with partial averaging

Analysis of PDEs 2017-03-08 v2

Abstract

A cross-diffusion system for two compoments with a Laplacian structure is analyzed on the multi-dimensional torus. This system, which was recently suggested by P.-L. Lions, is formally derived from a Fokker-Planck equation for the probability density associated to a multi-dimensional It\={o} process, assuming that the diffusion coefficients depend on partial averages of the probability density with exponential weights. A main feature is that the diffusion matrix of the limiting cross-diffusion system is generally neither symmetric nor positive definite, but its structure allows for the use of entropy methods. The global-in-time existence of positive weak solutions is proved and, under a simplifying assumption, the large-time asymptotics is investigated.

Keywords

Cite

@article{arxiv.1601.05039,
  title  = {A cross-diffusion system derived from a Fokker-Planck equation with partial averaging},
  author = {Ansgar Jüngel and Nicola Zamponi},
  journal= {arXiv preprint arXiv:1601.05039},
  year   = {2017}
}
R2 v1 2026-06-22T12:32:52.132Z