Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Schwarzschild black hole perturbed by a force-free magnetic field   We envisage a black hole perturbed by a force-free magnetic field (FFMF)
outside and attempt to determine its structure. We suppose the metric that
describes this black hole is of the static spherical type, that is
Schwarzschild, and the energy-momentum tensor emanating from an FFMF source
perturbs this background metric, in this regard one can imagine a magnetic
accretion disk around the black hole. By solving the equations for such a
configuration, we will show that in addition to modifying the diagonal elements
of the background metric, we will also see the non-zeroing of the off-diagonal
elements of the general metric, one of the immediate consequences of which will
be a static to stationary transition.

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The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
18
The categories of this paper are: econ
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom