Chaotic dynamics and superdiffusion in a Hamiltonian system with many degrees of freedom

V. Latora; A. Rapisarda; S. Ruffo

doi:10.1016/s0378-4371(99)00621-4

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arXiv · cond-mat/9911317

Chaotic dynamics and superdiffusion in a Hamiltonian system with many degrees of freedom

V. Latora·A. Rapisarda·S. Ruffo

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Abstract

We discuss recent results obtained for the Hamiltonian Mean Field model. The model describes a system of N fully-coupled particles in one dimension and shows a second-order phase transition from a clustered phase to a homogeneous one when the energy is increased. Strong chaos is found in correspondence to the critical point on top of a weak chaotic regime which characterizes the motion at low energies. For a small region around the critical point, we find anomalous (enhanced) diffusion and Lévy walks in a transient temporal regime before the system relaxes to equilibrium.

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V. Latora, A. Rapisarda, S. Ruffo. 1999-11-19. Chaotic dynamics and superdiffusion in a Hamiltonian system with many degrees of freedom. https://doi.org/10.1016/s0378-4371(99)00621-4

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