Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On periodic orbits in cotangent bundles of non-compact manifolds   This paper is concerned with the existence of periodic orbits on energy
hypersurfaces in cotangent bundles of Riemannian manifolds defined by
mechanical Hamiltonians. In \cite{bpv} it was proved that, provided certain
geometric assumptions are satisfied, regular mechanical hypersurfaces in
$\mathbb{R}^{2n}$, in particular non-compact ones, contain periodic orbits if
one homology group among the top half does not vanish. In the present paper we
extend the above mentioned existence result to a class of hypersurfaces in
cotangent bundles of Riemannian manifolds with flat ends.

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The categories of this paper are: q-fin
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
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The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
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The categories of this paper are: econ
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The categories of this paper are: solv-int
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The categories of this paper are: alg-geom
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The categories of this paper are: atom-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ex
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The categories of this paper are: eess
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The categories of this paper are: chem-ph
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The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph