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C2 densely the 2-sphere has an elliptic closed geodesic

Gonzalo Contreras·Fernando Oliveira
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Abstract

We prove that a riemannian metric on the 2-sphere or the projective plane can be C2-approximated by a smooth metric whose geodesic flow has an elliptic closed geodesic.

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Gonzalo Contreras, Fernando Oliveira. 2003-11-29. C2 densely the 2-sphere has an elliptic closed geodesic. https://arxiv.org/abs/math/0312005

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