Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Magnetic Rayleigh-Taylor Instability in Three Dimensions   We study the magnetic Rayleigh-Taylor instability in three dimensions, with
focus on the nonlinear structure and evolution that results from different
initial field configurations. We study strong fields in the sense that the
critical wavelength l_c at which perturbations along the field are stable is a
large fraction of the size of the computational domain. We consider magnetic
fields which are initially parallel to the interface, but have a variety of
configurations, including uniform everywhere, uniform in the light fluid only,
and fields which change direction at the interface. Strong magnetic fields do
not suppress instability, in fact by inhibiting secondary shear instabilities,
they reduce mixing between the heavy and light fluid, and cause the rate of
growth of bubbles and fingers to increase in comparison to hydrodynamics.
Fields parallel to, but whose direction changes at, the interface produce long,
isolated fingers separated by the critical wavelength l_c, which may be
relevant to the morphology of the optical filaments in the Crab nebula.

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The categories of this paper are: gr-qc
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The categories of this paper are: nucl-th
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The categories of this paper are: plasm-ph
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The categories of this paper are: physics
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The categories of this paper are: patt-sol
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The categories of this paper are: solv-int
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The categories of this paper are: atom-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: stat
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The categories of this paper are: dg-ga
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The categories of this paper are: cs
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The categories of this paper are: nlin
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-lat
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The categories of this paper are: funct-an
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The categories of this paper are: quant-ph