Absence of thermalization for systems with long-range interactions coupled to a thermal bath

摘要

We investigate the dynamics of a small long-range interacting system, incontact with a large long-range thermal bath. Our analysis reveals theexistence of striking anomalies in the energy flux between the bath and thesystem. In particular, we find that the evolution of the system is notinfluenced by the kinetic temperature of the bath, as opposed to what happensfor short-range collisional systems. As a consequence, the system may gethotter also when its initial temperature is larger than the bath temperature.This observation is explained quantitatively in the framework of thecollisionless Vlasov description of toy models with long-range interactions andshown to be valid whenever the Vlasov picture applies, from cosmology to plasmaphysics.