Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Regularization in the Restricted Four Body Problem   The restricted (equilateral) four-body problem consists of three bodies of
masses m1, m2 and m3 (called primaries) lying in a Lagrangian config- uration
of the three-body problem, i,e,. they remain fixed at the apices of an
equilateral triangle in a rotating coordinate system. A massless fourth body
moves under the Newtonian gravitation law due to the three pri- maries; as in
the restricted three-body problem the fourth mass does not affect the motion of
the three primaries. In this paper we show a global regularization of binary
collisions of the infinitesimal body with two of the primaries.

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The categories of this paper are: quant-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: cs
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
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The categories of this paper are: nlin
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The categories of this paper are: alg-geom
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The categories of this paper are: ao-sci
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The categories of this paper are: math-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: astro-ph
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The categories of this paper are: econ
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The categories of this paper are: hep-lat
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The categories of this paper are: patt-sol
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The categories of this paper are: cond-mat
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The categories of this paper are: acc-phys