Out-of-Equilibrium Dynamics in Systems with Long-Range Interactions: Characterizing Quasi-stationary States
Systems with long-range interactions (LRI) display unusual thermodynamical and dynamical properties that stem from the non-additive character of the interaction potential. We focus in this work on the lack of relaxation to thermal equilibrium when a LRI system is started out-of-equilibrium. Several attempts have been made at predicting the so-called quasi-stationary state (QSS) reached by the dynamics and at characterizing the resulting transition between magnetized and non-magnetized states. We review in this work recent theories and interpretations about the QSS. Several theories exist but none of them has provided yet a full account of the dynamics found in numerical simulations.
KeywordsVlasov equation Long-range interactions
The author would like to acknowledge interesting discussions and collaborations with R. Bachelard, G. De Ninno, D. Fanelli, P. Gaspard, D. Mukamel and S. Ruffo.