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Collective motion in a Hamiltonian dynamical system

Hidetoshi Morita·Kunihiko Kaneko
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Abstract

Oscillation of macroscopic variables is discovered in a metastable state in the Hamiltonian dynamical system of mean field XY model, the duration of which is divergent with the system size. This long-lasting periodic or quasiperiodic collective motion appears through Hopf bifurcation, which is a typical route in low-dimensional dissipative dynamical systems. The origin of the oscillation is explained, with self-consistent analysis of the distribution function, as the emergence of self-excited ``swings'' through the mean-field. The universality of the phenomena is also discussed.

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Hidetoshi Morita, Kunihiko Kaneko. 2005-06-11. Collective motion in a Hamiltonian dynamical system. https://arxiv.org/abs/cond-mat/0506261

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