- Ensemble Dynamics: From Trajectories to Diffusion and Kinetics
In this chapter, we shall take the final fundamental theoretical step in the statistical physics of biomolecules. We have already discussed how equilibrium phenomena are caused by dynamics, and we have carefully constructed an ensemble view of equilibrium behavior. We will now extend that ensemble view to dynamics. Typical biomolecular systems of interest, after all, do not perform dynamical processes just once but millions, billions, or trillions of times-or perhaps more. In a single living cell, further, there generally will be many copies of each molecule, although the number will fluctuate as the cell responds to external conditions or proceeds through the cell cycle. An ensemble picture, therefore, is perfectly natural.