Transition paths are hot

Abstract

Transition paths in a one-dimensional double-well potential are studied by Brownian dynamics simulations. For large mass and high barrier the velocity distribution of transition paths deviates significantly from the equilibrium Maxwell distribution and their effective temperature at the initial position in the potential well reaches many times the ambient temperature. The effective transition path temperature at the barrier top is only slightly increased and turns out to be maximal at intermediate values of the mass. An analytic expression for the temperature evolution along a transition path in the high-mass limit is derived.