Fluctuations of rotational and translational degrees of freedom in an interacting active dumbbell system

TL;DR

This paper investigates the fluctuations in translational and rotational motions of active dumbbells in a 2D system, analyzing how these fluctuations depend on activity level and density, revealing insights into their dynamical behavior.

Contribution

It provides a detailed analysis of fluctuation distributions in an active dumbbell system, extending previous work on mean-square displacements to include probabilistic behavior.

Findings

Fluctuation distributions depend on Péclet number and density.

Rotational and translational fluctuations show distinct behaviors.

Active forces significantly influence fluctuation characteristics.

Abstract

We study the dynamical properties of a two-dimensional ensemble of self-propelled dumbbells with only repulsive interactions. After summarizing the behavior of the translational and rotational mean-square displacements in the homogeneous phase that we established in a previous study, we analyze their fluctuations. We study the dependence of the probability distribution functions in terms of the P\'eclet number, describing the relative role of active forces and thermal fluctuations, and of particle density.