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Existence and continuation of periodic solutions of Newtonian systems

J. Fura·A. Ratajczak·S. Rybicki
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Abstract

In this article we study the existence and the continuation of periodic solutions of autonomous Newtonian systems. To prove the results we apply the infinite-dimensional version of the degree for SO(2)-equivariant gradient operators. Using the results due to Rabier we show that the Leray-Schauder degree is not applicable in the proofs of our theorems, because it vanishes.

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J. Fura, A. Ratajczak, S. Rybicki. 2006-04-12. Existence and continuation of periodic solutions of Newtonian systems. https://arxiv.org/abs/math/0604286

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