Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comment on "The complete Schwarzschild interior and exterior solution in
  the harmonic coordinate system" [J. Math. Phys. 39, 6086 (1998)]   In a recent paper Liu considered the complete Schwarzschild interior and
exterior solution in harmonic coordinates. There he argued about the necessity
to keep an integration constant, in contrast with previous treatments. The
purpose of this comment is to show that the above conclusion cannot be traced
from the matching conditions between the vacuum exterior and the uniform
density interior perfect fluid, as claimed.

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The categories of this paper are: chem-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: adap-org
14
The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
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The categories of this paper are: solv-int
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The categories of this paper are: acc-phys
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-th
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The categories of this paper are: mtrl-th
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The categories of this paper are: alg-geom
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The categories of this paper are: dg-ga
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The categories of this paper are: q-alg
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The categories of this paper are: patt-sol
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The categories of this paper are: econ