TASEP with a general initial condition and a deterministically moving wall

TL;DR

This paper analyzes the TASEP with general initial conditions and a moving wall, deriving formulas for particle distributions, studying asymptotics, and identifying shock-related limit distributions.

Contribution

It introduces a new formula linking general initial conditions to step initial condition TASEP, enabling detailed asymptotic analysis and shock distribution characterization.

Findings

Distinct asymptotic behaviors at the wall boundary for non-step initial conditions

Product limit distributions associated with shocks in the empirical density

A variational formula for one-point distributions with arbitrary initial data

Abstract

We study the totally asymmetric simple exclusion process (TASEP) on $\mathbb{Z}$ with a general initial condition and a deterministically moving wall in front of the particles. Using colour-position symmetry, we express the one-point distributions in terms of particle positions in a TASEP with step initial condition along a space-like path. Based on this formula, we analyse the large-time asymptotics of the model under various scenarios. For initial conditions other than the step initial condition, we identify a distinct asymptotic behaviour at the boundary of the region influenced by the wall, differing from the observations made in [Borodin-Bufetov-Ferrari'24] and [Ferrari-Gernholt'24]. Furthermore, we demonstrate that product limit distributions are associated with shocks in the macroscopic empirical density. As a special case of our starting formula, we derive a variational expression for the one-point distributions of TASEP with arbitrary initial data. Focusing on non-random initial conditions, such as periodic ones with an arbitrary density, we leverage our analytical tools to characterise the limit distribution within the framework of particle positions.