  We present results of molecular simulations of a model protein whose
hydrophobic collapse proceeds as a cascade of downhill transitions between
distinct intermediate states. Different intermediates are stabilized by means
of appropriate harmonic constraints, allowing explicit calculation of the
equilibrium free energy landscape. Nonequilibrium collapse trajectories are
simulated independently and compared to diffusion on the calculated free energy
surface. We find that collapse generally adheres to this surface, but
quantitative agreement is complicated by nonequilibrium effects and by
dependence of the diffusion coefficient on position on the surface.
