Lattice gases with a point source

TL;DR

This paper analyzes how particle injection at a point affects the behavior of diffusive lattice gases, revealing collective interactions and quantifying particle entry and site visitation in symmetric exclusion and random walk models.

Contribution

It introduces a model of lattice gases with point source injection and derives key statistical properties, highlighting collective effects even in non-interacting systems.

Findings

Average total number of particles injected is computed.

Number of distinct visited sites is determined.

Visited domain shape and visit statistics are discussed.

Abstract

We study diffusive lattice gases with local injection of particles, namely we assume that whenever the origin becomes empty, a new particle is immediately injected into the origin. We consider two lattice gases: a symmetric simple exclusion process and random walkers. The interplay between the injection events and the positions of the particles already present implies an effective collective interaction even for the ostensibly non-interacting random walkers. We determine the average total number of particles entering into the initially empty system. We also compute the average total number of distinct sites visited by all particles, and discuss the shape of the visited domain and the statistics of visits.