# Microscopic reweighting for non-equilibrium steady states dynamics

## TL;DR

This paper develops a method to reweight and analyze non-equilibrium steady states in simulations by extending equilibrium statistical reweighting techniques using a maximum path entropy approach and stochastic thermodynamics.

## Contribution

It introduces a novel framework for reweighting non-equilibrium steady states based on path entropy and Markovian pathways, bridging a gap in simulation analysis.

## Key findings

- Reweighting in and out of equilibrium using path probabilities.
- Identification of an invariant quantity analogous to density of states.
- Systematic construction of pathways through Markovian transitions.

## Abstract

Computer simulations generate trajectories at a single, well-defined thermodynamic state point. Statistical reweighting offers the means to reweight static and dynamical properties to different equilibrium state points by means of analytic relations. We extend these ideas to non-equilibrium steady states by relying on a maximum path entropy formalism subject to physical constraints. Stochastic thermodynamics analytically relates the forward and backward probabilities of any pathway through the external non-conservative force, enabling reweighting both in and out of equilibrium. We avoid the combinatorial explosion of microtrajectories by systematically constructing pathways through Markovian transitions. We further identify a quantity that is invariant to dynamical reweighting, analogous to the density of states in equilibrium reweighting.