We elucidate the connection between various fluctuation theorems by a microcanonical version of the Crooks relation. We derive the microscopically exact expression for the work distribution in an idealized Joule experiment, namely, for a convex object moving at constant speed through an ideal gas. Analytic results are compared with molecular dynamics simulations of a hard disk gas.

• Received 7 November 2005

DOI:https://doi.org/10.1103/PhysRevLett.96.050601