UC Berkeley

Rare events are ubiquitous in noisy complex systems throughout the physical sciences and to large extent determine their function and regulation. Dissipative outside forces often work hand in hand with equilibrium structure to shape the mechanism and frequency of such improbable fluctuations, but little is known about how to codify the influence of non-equilibrium on reaction rates and their mechanisms. In the last quarter century we have seen paradigm shifting breakthroughs in reaction rate theory that have allowed for the study of rare transitions in complex many particle systems. At the same time, development of the statistical mechanics of trajectories has revolutionized how we study the behavior, response and functional limits of systems away from equilibrium. Here, we develop a trajectory theory of how reaction rates respond to nonequilibrium forces, allowing us both to probe how non-equilibrium systems regulate their function, and leverage optimally designed forces to sample reaction rates from finite time driven trajectories for the first time.