Physics – Condensed Matter – Soft Condensed Matter
Scientific paper
2007-07-15
Physics
Condensed Matter
Soft Condensed Matter
18 pages, 8 figures, Accepted to PRE
Scientific paper
10.1103/PhysRevE.76.011123
The friction coefficient of a particle can depend on its position as it does when the particle is near a wall. We formulate the dynamics of particles with such state-dependent friction coefficients in terms of a general Langevin equation with multiplicative noise, whose evaluation requires the introduction of specific rules. Two common conventions, the Ito and the Stratonovich, provide alternative rules for evaluation of the noise, but other conventions are possible. We show the requirement that a particle's distribution function approach the Boltzmann distribution at long times dictates that a drift term must be added to the Langevin equation. This drift term is proportional to the derivative of the diffusion coefficient times a factor that depends on the convention used to define the multiplicative noise. We explore the consequences of this result in a number examples with spatially varying diffusion coefficients. We also derive path integral representations for arbitrary interpretation of the noise, and use it in a perturbative study of correlations in a simple system.
Lau A. W. C.
Lubensky Tom. C.
No associations
LandOfFree
State-dependent diffusion: thermodynamic consistency and its path integral formulation does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with State-dependent diffusion: thermodynamic consistency and its path integral formulation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and State-dependent diffusion: thermodynamic consistency and its path integral formulation will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-449799