Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Rayleigh-Taylor Instability in Viscoelastic Fluids   In this paper I analyze the onset of Rayleigh-Taylor instability between two
linear viscoelastic fluids assuming that the perturbations at the interface are
small. In the first half, the paper analyzes a stratified viscoelastic fluid in
which I prove that the perturbations rise or fall exponentially without
oscillating. The second half of the paper examines the effect of electric and
magnetic fields on viscoelastic fluids. I show that it is possible to choose
electric or magnetic field gradient such that the effective acceleration due to
gravity is zero. If a heavy Newtonian fluid rests on top of a lighter Newtonian
fluid such a choice of field gradient would have rendered the arrangement
stable. If the fluids are viscoelastic, I show that a similar arrangement is
unstable.

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The categories of this paper are: q-bio
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The categories of this paper are: mtrl-th
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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: chao-dyn
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The categories of this paper are: atom-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: plasm-ph
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The categories of this paper are: q-alg
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The categories of this paper are: hep-ph
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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: ao-sci
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-th
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The categories of this paper are: nlin