Breakdown of Gallavotti-Cohen symmetry for stochastic dynamics
  We consider the behaviour of current fluctuations in the one-dimensional partially asymmetric zero-range process with open boundaries. Significantly, we find that the distribution of large current fluctuations does not satisfy the Gallavotti-Cohen symmetry and that such a breakdown can generally occur in systems with unbounded state space. We also discuss the dependence of the asymptotic current distribution on the initial state of the system. 
R. J. Harris, A. R\'akos, G. M. Schuetz