Frenesy

Christian Maes

Published 2019-04-23Version 1

Dynamical ensembles of nonequilibrium statistical mechanics are specified from an action functional or Lagrangian on spacetime. Frenesy is the time-symmetric part of that path-space action with respect to a reference process. It collects the variable quiescence and dynamical activity as function of the system's trajectory. We discuss its various realizations for physically inspired Markov jump and diffusion processes and why it matters a good deal for nonequilibrium physics. This review serves as an introduction to the exploration of frenetic contributions in nonequilibrium phenomena.