Global fluctuations in dissipative systems

Abstract

Our goal here is to investigate the influence of velocity correlations on the fluctuations of several global quantities for two different systems. In the first case, we study the fluctuations of the total number of particles, momentum and energy in a probabilistic ballistic annihilation model. For this model, when there is a binary encounter, the particles annihilate with certain probability. In the second case, we analyze the fluctuations of the total energy in a granular system which is driven by a stochastic thermostat. The theoretical analysis is based on the study of the equation for the two-particle distribution function. The predictions are in very good agreement with simulations results.