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arXiv · 2009.14032

Inertial self-propelled particles

Lorenzo Caprini·Umberto Marini Bettolo Marconi
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Abstract

We study a self-propelled particle moving in a solvent with the active Ornstein Uhlenbeck dynamics in the underdamped regime to evaluate the influence of the inertia. We focus on the properties of potential-free and harmonically confined underdamped active particles, studying how the single-particle trajectories modify for different values of the drag coefficient. In both cases, we solve the dynamics in terms of correlation matrices and steady-state probability distribution functions revealing the explicit correlations between velocity and active force. We also evaluate the influence of the inertia on the time-dependent properties of the system, discussing the mean square displacement and the time-correlations of particle positions and velocities. Particular attention is devoted to the study of the Virial active pressure unveiling the role of the inertia on this observable.

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BibTeXRIS

Lorenzo Caprini, Umberto Marini Bettolo Marconi. 2020-09-29. Inertial self-propelled particles. https://doi.org/10.1063/5.0030940

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