Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Supermassive Black Hole Binaries: The Search Continues   Gravitationally bound supermassive black hole binaries (SBHBs) are thought to
be a natural product of galactic mergers and growth of the large scale
structure in the universe. They however remain observationally elusive, thus
raising a question about characteristic observational signatures associated
with these systems. In this conference proceeding I discuss current theoretical
understanding and latest advances and prospects in observational searches for
SBHBs.

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The categories of this paper are: hep-th
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The categories of this paper are: ao-sci
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The categories of this paper are: chem-ph
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The categories of this paper are: stat
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The categories of this paper are: q-alg
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The categories of this paper are: mtrl-th
24
The categories of this paper are: dg-ga
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The categories of this paper are: hep-ph
23
The categories of this paper are: solv-int
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The categories of this paper are: math-ph
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The categories of this paper are: adap-org
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The categories of this paper are: comp-gas
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The categories of this paper are: q-fin
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The categories of this paper are: patt-sol
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-ex