Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Charged black holes in quadratic gravity   Iterative solutions to fourth-order gravity describing static and
electrically charged black holes are constructed. Obtained solutions are
parametrized by two integration constants which are related to the electric
charge and the exact location of the event horizon. Special emphasis is put on
the extremal black holes. It is explicitly demonstrated that in the extremal
limit, the exact location of the (degenerate) event horizon is given by $\rp =
|e|.$ Similarly to the classical Reissner-Nordstr\"om solution, the
near-horizon geometry of the charged black holes in quadratic gravity, when
expanded into the whole manifold, is simply that of Bertotti and Robinson.
Similar considerations have been carried out for the boundary conditions of
second type which employ the electric charge and the mass of the system as seen
by a distant observer. The relations between results obtained within the
framework of each method are briefly discussed.

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The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
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The categories of this paper are: physics
29
The categories of this paper are: funct-an
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The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol