Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Regular black holes with flux tube core   We consider a class of black holes for which the area of the two-dimensional
spatial cross-section has a minimum on the horizon with respect to a
quasiglobal (Krusckal-like) coordinate. If the horizon is regular, one can
generate a tubelike counterpart of such a metric and smoothly glue it to a
black hole region. The resulting composite space-time is globally regular, so
all potential singuilarities under the horizon of the original metrics are
removed. Such a space-time represents a black hole without an apparent horizon.
It is essential that the matter should be non-vacuum in the outer region but
vacuumlike in the inner one. As an example we consider the noninteracting
mixture of vacuum fluid and matter with a linear equation of state and scalar
phantom fields. This approach is extended to distorted metrics, with the
requirement of spherical symmetry relaxed.

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The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
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The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
4
The categories of this paper are: cond-mat
10
The categories of this paper are: q-bio
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
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The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex