# Entropy production and fluctuation theorems for active matter

## TL;DR

This paper extends stochastic thermodynamics to active matter, defining thermodynamic quantities and fluctuation relations for non-equilibrium active systems, and demonstrates these concepts through numerical simulations.

## Contribution

It introduces a framework for thermodynamic analysis of active matter, including definitions of work, heat, and entropy production, and generalizes fluctuation theorems and inequalities.

## Key findings

- Defined thermodynamic quantities for active Ornstein-Uhlenbeck models
- Derived fluctuation relations applicable to active matter
- Numerical validation of theoretical results

## Abstract

Active biological systems reside far from equilibrium, dissipating heat even in their steady state, thus requiring an extension of conventional equilibrium thermodynamics and statistical mechanics. In this Letter, we have extended the emerging framework of stochastic thermodynamics to active matter. In particular, for the active Ornstein-Uhlenbeck model, we have provided consistent definitions of thermodynamic quantities such as work, energy, heat, entropy, and entropy production at the level of single, stochastic trajectories and derived related fluctuation relations. We have developed a generalization of the Clausius inequality, which is valid even in the presence of the non-Hamiltonian dynamics underlying active matter systems. We have illustrated our results with explicit numerical studies.