Langevin dynamics random force term generation algorithm

iibewegung
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Hi,

Can anyone tell me an algorithm to generate the stationary Gaussian distribution R(t) with

\langle R(t) \rangle = 0 (zero mean)
\langle R(t) R(t')^{T} \rangle = A \delta(t-t'), A = 2 \gamma k_B T m (autocorrelation)

?

What I just wrote is from the Wikipedia article "Langevin dynamics"
and R(t) belongs to the simple Langevin equation
F(x) = m \ddot{x} = -\nabla U(x) - \gamma m \dot{x} + R(t)
 
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I have been looking for the same code. It is not exactly trivial. I found some code in the following book
"The Molecular Dynamics of Liquid Crystals,by G. R. Luckhurst, C. A. Veracini"
I have been looking for a DJVU copy of this book but haven't found one.
 
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