Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The compactification of initial data on constant mean curvature time
  slices in spherically symmetric spacetimes   Conformal mappings of surfaces of constant mean curvature onto compact
bounded background spaces are constructed for Minkowski space-time and for
Schwarzschild black hole spacetimes. In the black hole example, it is found
that initial data on these CMC surfaces can be regular on the compact
background space only when a certain condition is satisfied. That condition
implies that the shift vector points inward from all parts of the boundary of
the compact background. It also implies that the second fundamental form of
these surfaces can never be isotropic when black holes are present.

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The categories of this paper are: nlin
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
4
The categories of this paper are: cond-mat
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The categories of this paper are: nucl-th
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The categories of this paper are: stat
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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: hep-lat
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The categories of this paper are: q-alg
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The categories of this paper are: physics
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The categories of this paper are: atom-ph
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The categories of this paper are: funct-an
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The categories of this paper are: chao-dyn
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The categories of this paper are: math
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The categories of this paper are: chem-ph