Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Regular charged black hole construction in 2+1 -dimensions   It is well-known that unlike its chargeless version the charged
Banados-Teitelboim-Zanelli (BTZ) black hole solution in 2+1- dimensional
spacetime is singular. We construct a charged, regular extension of the BTZ
black hole solution by employing nonlinear Born-Infeld electrodynamics,
supplemented with the Hoffmann term and gluing different spacetimes. The role
of the latter term is to divide spacetime in a natural way into two regions by
a circle and eliminate the inner singularity. Thermodynamics of such a black
hole is investigated by Kaluza-Klein reduction to the 1+1-dimensional dilaton
gravity.

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The categories of this paper are: stat
19
The categories of this paper are: eess
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
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The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
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The categories of this paper are: q-bio
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The categories of this paper are: econ
34
The categories of this paper are: chem-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: comp-gas
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The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys