Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Gravitational Waves in Brane World -A Midi-superspace Approach-   It is important to reveal the brane-bulk correspondence for understanding the
brane world cosmology. When gravitational waves exist in the bulk, however, it
is difficult to make the analysis of the interrelationship between the brane
and the bulk. Hence, the minimal model which allows gravitational waves in the
bulk would be useful. As for such models, we adopt the Bianchi type
midi-superspace models. In particular, the effects of gravitational waves in
the bulk on the brane cosmology is examined using the midi-superspace approach.

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The categories of this paper are: dg-ga
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The categories of this paper are: funct-an
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
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The categories of this paper are: adap-org
14
The categories of this paper are: math-ph
4
The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph
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The categories of this paper are: q-bio
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The categories of this paper are: quant-ph
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The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
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The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
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The categories of this paper are: mtrl-th
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The categories of this paper are: nucl-ex