Affiliations 

  • 1 The Rockefeller University, New York, New York 10065, USA
  • 2 Dipartimento di Scienze Matematiche and Graphene@Polito Lab Politecnico di Torino - Corso Duca degli Abruzzi 24, 10125, Torino, Italy
Phys Rev E, 2016 Sep;94(3-1):032127.
PMID: 27739763

Abstract

In this paper, we generalize the theory of Brownian motion and the Onsager-Machlup theory of fluctuations for spatially symmetric systems to equilibrium and nonequilibrium steady-state systems with a preferred spatial direction, due to an external force. To do this, we extend the Langevin equation to include a bias, which is introduced by an external force and alters the Gaussian structure of the system's fluctuations. In addition, by solving this extended equation, we provide a physical interpretation for the statistical properties of the fluctuations in these systems. Connections of the extended Langevin equation with the theory of active Brownian motion are discussed as well.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.