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Published on: December 4, 2017
Abundance of regular orbits and nonequilibrium phase transitions in the thermodynamic limit for long-range systems
R Bachelard1, C Chandre, D Fanelli
1Centre de Physique Théorique, CNRS--Aix-Marseille Université, Luminy, Case 907, F-13288 Marseille cedex 9, France.
Abstract:
We investigate the dynamics of many-body long-range interacting systems, taking the Hamiltonian mean-field model as a case study. We show that regular trajectories, associated with invariant tori of the single-particle dynamics, prevail. The presence of such tori provides a dynamical interpretation of the emergence of long-lasting out-of-equilibrium regimes observed generically in long-range systems. This is alternative to a previous statistical mechanics approach to such phenomena which was based on a maximum entropy principle. Previously detected out-of-equilibrium phase transitions are also reinterpreted within this framework.
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