Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic field reversals and topological entropy in non-geodesic
  hyperbolic dynamos   Earlier, Chicone, Latushkin and Montgomery-Smith [Comm Math Phys (1997)] have
proved the existence of a fast dynamo operator, in compact two-dimensional
manifold, as long as its Riemannian curvature be constant and negative. More
recently Gallet and Petrelis [Phys Rev \textbf{E}, 80 (2009)] have investigated
saddle-node bifurcation, in turbulent dynamos as modelling for magnetic field
reversals. Since saddle nodes are created in hyperbolic flows, this provides us
with physical motivation to investigate these reversals in a simple kinematic
dynamo model obtained from a force-free non-geodesic steady flow in Lobachevsky
plane. Magnetic vector potential grows in one direction and decays in the other
under diffusion. Magnetic field differential 2-form is orthogonal to the plane.
A restoring forcing dynamo in hyperbolic space is also given. Magnetic field
reversals are obtained from this model. Topological entropies [Klapper and
Young, Comm Math Phys (1995)] are also computed.

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The categories of this paper are: nucl-ex
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The categories of this paper are: atom-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: econ
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The categories of this paper are: stat
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The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
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The categories of this paper are: adap-org
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The categories of this paper are: q-bio
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The categories of this paper are: astro-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: gr-qc
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The categories of this paper are: q-alg
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The categories of this paper are: eess
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The categories of this paper are: nucl-th
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The categories of this paper are: cs