FLUCTUATION AND DISSIPATION IN CLASSICAL MANY-PARTICLE SYSTEMS

Coarse-grained Langevin-type effective field equations are derived for classical systems of particles. These equations include the effects o f thermal fluctuation and dissipation that may arise from coupling to an external bath, as in the Brownian motion of a single particle, or f rom statistical fluctuations in small parts of an isolated many-partic le system, as in sound waves. These equations may provide some guidanc e for the analysis of mesoscopic or microscopic molecular systems or f or systems of hundreds to thousands of subatomic particles produced in high-energy nuclear collisions.