Universal decay of the classical Loschmidt echo of neutrally stable mixing dynamics

Abstract

We provide analytical and numerical evidence that the classical mixing systems, which lack exponential sensitivity on initial conditions, exhibit universal decay of the Loschmidt echo which turns out to be a function of a single scaled time variable δ2/5t, where δ is the strength of perturbation. The role of dynamical instability and entropy production is discussed. © 2005 The American Physical Society.