Multidimensional entropic bound: Estimator of entropy production for general Langevin dynamics with an arbitrary time-dependent protocol

TL;DR

The paper introduces a versatile and efficient estimator for entropy production in Langevin systems that works without detailed system knowledge and applies to various physical scenarios with time-dependent driving.

Contribution

It presents the multidimensional entropic bound (MEB), a novel entropy production estimator applicable to both overdamped and underdamped Langevin dynamics with arbitrary protocols, without requiring optimization.

Findings

MEB accurately estimates entropy production in simulated systems.

The method is computationally efficient and applicable to experimental data.

Validation on optical tweezer experiments confirms its practical utility.

Abstract

Entropy production (EP) is a key quantity in thermodynamics, and yet measuring EP has remained a challenging task. Here we introduce an EP estimator, called multidimensional entropic bound (MEB), utilizing an ensemble of trajectories without knowing the details of a given system. MEB is a unified method in the sense that it is applicable to both overdamped and underdamped Langevin dynamics, irrespective of the time dependence of the driving protocol. In addition, MEB is computationally efficient because optimization is unnecessary. We apply our developed estimator to three physical systems driven by time-dependent protocols pertaining to experiments using optical tweezers: a dragged Brownian particle, a pulling process of a harmonic chain, and an unfolding process of an RNA hairpin. Numerical simulations confirm the validity and efficiency of our method.