Strong fluctuation theorem for nonstationary nonequilibrium systems

We present a finite-time detailed fluctuation theorem of the form (P) over tilde(Delta S-env) = e(Delta Senv)(P) over tilde(-Delta S-env) for an appropriately weighted probability density (P) over tilde(Delta S-env) of the external entropy production in the environment Delta S-env. The fluctuation theorem is valid for nonequilibrium systems with constant rates starting with an arbitrary initial probability distribution. We discuss the implication of this relation for the case of a temperature quench in classical equilibrium systems. The fluctuation theorem is tested numerically for a Markov jump process with six states and for a surface growth model. DOI: 10.1103/PhysRevE.87.042108