English

Reaction-diffusion on the fully-connected lattice: $A+A\rightarrow A$

Statistical Mechanics 2018-03-13 v1

Abstract

Diffusion-coagulation can be simply described by a dynamic where particles perform a random walk on a lattice and coalesce with probability unity when meeting on the same site. Such processes display non-equilibrium properties with strong fluctuations in low dimensions. In this work we study this problem on the fully-connected lattice, an infinite-dimensional system in the thermodynamic limit, for which mean-field behaviour is expected. Exact expressions for the particle density distribution at a given time and survival time distribution for a given number of particles are obtained. In particular we show that the time needed to reach a finite number of surviving particles (vanishing density in the scaling limit) displays strong fluctuations and extreme value statistics, characterized by a universal class of non-Gaussian distributions with singular behaviour.

Keywords

Cite

@article{arxiv.1711.01248,
  title  = {Reaction-diffusion on the fully-connected lattice: $A+A\rightarrow A$},
  author = {L. Turban and J. -Y. Fortin},
  journal= {arXiv preprint arXiv:1711.01248},
  year   = {2018}
}

Comments

24 pages, 9 figures

R2 v1 2026-06-22T22:35:31.847Z