Asymptotic limits of transient patterns in a continuous-space interacting particle system

TL;DR

This paper analyzes a continuous-space interacting particle system modeling actin filament turnover, characterizing its asymptotic cluster distributions and revealing fat-tailed aggregate distributions through recurrence relations.

Contribution

It introduces a novel formulation and analysis of a particle system with continuous states, deriving explicit distribution characterizations and moment computations for transient clusters.

Findings

Transient clusters resemble actin filament assemblies.

Aggregate distributions are fat-tailed.

Recurrence relations enable moment calculations.

Abstract

We study a discrete-time interacting particle system with continuous state space which is motivated by a mathematical model for turnover through branching in actin filament networks. It gives rise to transient clusters reminiscent of actin filament assemblies in the cortex of living cells. We reformulate the process in terms of the inter-particle distances and characterise their marginal and joint distributions. We construct a recurrence relation for the associated characteristic functions and pass to the large population limit, reminiscent of the Fleming-Viot super-processes. The precise characterisation of all marginal distributions established in this work opens the way to a detailed analysis of cluster dynamics. We also obtain a recurrence relation which enables us to compute the moments of the asymptotic single particle distribution characterising the transient aggregates. Our results indicate that aggregates have a fat-tailed distribution.