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Short geodesics losing optimality in contact sub-Riemannian manifolds and stability of the 5-dimensional caustic

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 نشر من قبل Ludovic Sacchelli
 تاريخ النشر 2018
  مجال البحث
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 تأليف Ludovic Sacchelli




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We study the sub-Riemannian exponential for contact distributions on manifolds of dimension greater or equal to 5. We compute an approximation of the sub-Riemannian Hamiltonian flow and show that the conjugate time can have multiplicity 2 in this case. We obtain an approximation of the first conjugate locus for small radii and introduce a geometric invariant to show that the metric for contact distributions typically exhibits an original behavior, different from the classical 3-dimensional case. We apply these methods to the case of 5-dimensional contact manifolds. We provide a stability analysis of the sub-Riemannian caustic from the Lagrangian point of view and classify the singular points of the exponential map.



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