Equilibrium and non-equilibrium fluctuations in a glass-forming liquid

Abstract

Glass-forming liquids display strong fluctuations -- dynamical heterogeneities -- near their glass transition. By numerically simulating a binary Weeks-Chandler-Andersen liquid and varying both temperature and timescale, we investigate the probability distributions of two kinds of local fluctuations in the non-equilibrium (aging) regime and in the equilibrium regime; and find them to be very similar in the two regimes and across temperatures. We also observe that, when appropriately rescaled, the integrated dynamic susceptibility is very weakly dependent on temperature and very similar in both regimes.Comment: v1: 5 pages, 4 figures v2: 5 pages, 4 figures. Now includes results at three temperatures, two of them above T_{MCT} and one below T_{MCT}; and more extensive discussion of connections to experiment