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arXiv · 1607.08440

A stability criterion for non-degenerate equilibrium states of completely integrable systems

Abstract

We provide a criterion in order to decide the stability of non-degenerate equilibrium states of completely integrable systems. More precisely, given a Hamilton-Poisson realization of a completely integrable system generated by a smooth $n-$ dimensional vector field, $X$, and a non-degenerate regular (in the Poisson sense) equilibrium state, $\overline{x}_e$, we define a scalar quantity, $\mathcal{I}_{X}(\overline{x}_e)$, whose sign determines the stability of the equilibrium. Moreover, if $\mathcal{I}_{X}(\overline{x}_e)>0$, then around $\overline{x}_e$ there exist one-parameter families of periodic orbits shrinking to $\{\overline{x}_e \}$, whose periods approach $2\pi/\sqrt{\mathcal{I}_{X}(\overline{x}_e)}$ as the parameter goes to zero. The theoretical results are illustrated in the case of the Rikitake dynamical system.

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BibTeXRIS

Razvan M. Tudoran. 2016-07-28. A stability criterion for non-degenerate equilibrium states of completely integrable systems. https://doi.org/10.1016/j.jde.2017.07.032

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