Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On universal black holes   Recent results of arXiv:1907.08788 on universal black holes in $d$ dimensions
are summarized. These are static metrics with an isotropy-irreducible
homogeneous base space which can be consistently employed to construct
solutions to virtually any metric theory of gravity in vacuum.

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The categories of this paper are: comp-gas
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The categories of this paper are: funct-an
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The categories of this paper are: eess
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The categories of this paper are: atom-ph
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The categories of this paper are: adap-org
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The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
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The categories of this paper are: quant-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: q-alg
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The categories of this paper are: solv-int
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The categories of this paper are: nucl-th
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The categories of this paper are: q-bio
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The categories of this paper are: dg-ga
9
The categories of this paper are: nlin