Dissipation Bounds All Steady-State Current Fluctuations

Phys Rev Lett. 2016 Mar 25;116(12):120601. doi: 10.1103/PhysRevLett.116.120601. Epub 2016 Mar 21.

Abstract

Near equilibrium, small current fluctuations are described by a Gaussian distribution with a linear-response variance regulated by the dissipation. Here, we demonstrate that dissipation still plays a dominant role in structuring large fluctuations arbitrarily far from equilibrium. In particular, we prove a linear-response-like bound on the large deviation function for currents in Markov jump processes. We find that nonequilibrium current fluctuations are always more likely than what is expected from a linear-response analysis. As a small-fluctuations corollary, we derive a recently conjectured uncertainty bound on the variance of current fluctuations.