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arXiv · 1607.01143

Symmetric Liapunov center theorem

Ernesto Pérez-Chavela·Sławomir Rybicki·Daniel Strzelecki
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Abstract

In this article, using an infinite-dimensional equivariant Conley index, we prove a generalization of the profitable Liapunov center theorem for symmetric potentials. Consider the system $\ddot{q}= -\nabla U(q),$ where $U(q)$ is a $\Gamma$-symmetric potential, where $\Gamma$ is a compact Lie group acting linearly on $\mathbb{R}^n$. If the system possess a non-degenerate orbit of stationary solutions $\Gamma(q_0)$ with trivial isotropy group, such that there exists at least one positive eigenvalue of the Hessian $\nabla^2 U(q_0)$, then in any neighbourhood of orbit $\Gamma(q_0)$ there is a periodic orbit of solutions of the system.

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Ernesto Pérez-Chavela, Sławomir Rybicki, Daniel Strzelecki. 2016-07-05. Symmetric Liapunov center theorem. https://doi.org/10.1007/s00526-017-1120-1

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