On the higher order corrections to the Fokker–Planck equation
نویسنده
چکیده
The Rayleigh model of nonlinear Brownian motion is revisited in which the heavy particle of mass M interacts with ideal gas molecules of mass m5M via instantaneous collisions. Using the van Kampen method of expansion of the master equation, nonlinear corrections to the Fokker–Planck equation are obtained up to sixth order in the small parameter l 1⁄4 ffiffiffiffiffiffiffiffiffiffiffi m=M p ; improving earlier results. The role and origin of non-Gaussian statistics of the random force in the corresponding Langevin equation are also discussed. r 2005 Elsevier B.V. All rights reserved.
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