vix.ing · top · new · best · stats · spec

Static vs dynamic rough energy landscapes: Where is diffusion faster?

2025/06/02 by Dmitrii E. Makarov, Peter Sollich, Makarov, Dmitrii E. +1
Physics and Astronomy · Engineering · #Theoretical and Computational Physics #Lattice Boltzmann Simulation Studies

paper · pdf · doi:10.48550/arxiv.2506.02195

Abstract

Molecules in dense environments, such as biological cells, are subjected to forces that fluctuate both in time and in space. While spatial fluctuations are captured by Lifson-Jackson-Zwanzig's model of "diffusion in a rough potential", and temporal fluctuations are often viewed as leading to additional friction effects, a unified view where the environment fluctuates both in time and in space is currently lacking. Here we introduce a discrete-state model of a landscape fluctuating both in time and in space. Importantly, the model accounts for the back-reaction of the diffusing particle on the landscape. As a result we find, surprisingly, that many features of the observable dynamics do not depend on the temporal fluctuation timescales and are already captured by the model of diffusion in a rough potential, even though this assumes a static energy landscape.

Related