Large deviations in boundary-driven systems: Numerical evaluation and   effective large-scale behavior
  We study rare events in systems of diffusive fields driven out of equilibrium by the boundaries. We present a numerical technique and use it to calculate the probabilities of rare events in one and two dimensions. Using this technique, we show that the probability density of a slowly varying configuration can be captured with a small number of long wave-length modes. For a configuration which varies rapidly in space this description can be complemented by a local equilibrium assumption. 
Guy Bunin, Yariv Kafri, and Daniel Podolsky
cond-mat.stat-mech