The fluctuation theorem and Lyapunov weights

The fluctuation theorem (FT) is a generalisation of the second law of thermodynamics that applies to small systems observed for short times. For thermostatted systems it gives the probability ratio that entropy will be consumed rather than produced. In this paper we derive the transient and steady state FTs using Lyapunov weights rather than the usual Gibbs weights. At long times the FTs so derived are identical to those derived using the more standard Gibbs weights. (C) 2003 Elsevier B.V. All rights reserved