Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Black Holes and Causal Structure in Anti-de Sitter Isometric Spacetimes   The observation that the 2+1 dimensional BTZ black hole can be obtained as a
quotient space of anti-de Sitter space leads one to ask what causal behaviour
other such quotient spaces can display. In this paper we answer this question
in 2+1 and 3+1 dimensions when the identification group has one generator.
Among other things we find that there does not exist any 3+1 generalization of
the rotating BTZ hole. However, the non-rotating generalization exists and
exhibits some unexpected properties. For example, it turns out to be non-static
and to possess a non-trivial apparent horizon.

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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: math
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The categories of this paper are: q-fin
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The categories of this paper are: nlin
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The categories of this paper are: hep-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-lat
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The categories of this paper are: nucl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-th
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
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The categories of this paper are: solv-int
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The categories of this paper are: atom-ph
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The categories of this paper are: eess