# Diffusion in deterministic interacting lattice systems

## TL;DR

This paper rigorously analyzes deterministic lattice systems with charged particles, revealing ballistic, diffusive, and insulating transport behaviors, and provides exact formulas for transport coefficients validated by simulations.

## Contribution

It offers the first exact analytical expressions for current autocorrelation and transport coefficients in a deterministic lattice model with interactions.

## Key findings

- Identifies three transport regimes: ballistic, diffusive, insulating.
- Derives exact formulas for diffusion constant and Drude weight.
- Validates analytical results with Monte-Carlo simulations.

## Abstract

We study reversible deterministic dynamics of classical charged particles on a lattice with hard-core interaction. It is rigorously shown that the system exhibits three types of transport phenomena, ranging from ballistic, through diffusive to insulating. By obtaining an exact expressions for the current time-autocorrelation function we are able to calculate the linear response transport coefficients, such as the diffusion constant and the Drude weight. Additionally, we calculate the long- time charge profile after an inhomogeneous quench and obtain diffusive profile with the Green-Kubo diffusion constant. Exact analytical results are corroborated by Monte-Carlo simulations.