Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Black Holes with Skyrme Hair   This paper is intended to give a review of the recent developments on black
holes with Skyrme hair. The Einstein-Skyrme system is known to possess black
hole solutions with Skyrme hair. The spherically symmetric black hole skyrmion
with B=1 was the first discovered counter example of the no-hair conjecture for
black holes. Recently we found the B=2 axially symmetric black hole skyrmion.
In this system, the black hole at the center of the skyrmion absorbs the baryon
number partially, leaving fractional charge outside the horizon. Therefore the
baryon number is no longer conserved. We examine the B=1, 2 black hole
solutions in detail in this paper. The model has a natural extension to the
gauged version which can describe monopole black hole skyrmions. Callan and
Witten discussed the monopole catalysis of proton decay within the Skyrme
model. We apply the idea to the Einstein-Maxwell-Skyrme system and obtain
monopole black hole skyrmions. Remarkably there exist multi-black hole skyrmion
solutions in which the gravitational, electromagnetic, and strong forces
between the monopoles are all in balance. The solutions turn out to be stable
under spherically symmetric linear perturbations.

14
The categories of this paper are: math-ph
21
The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
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The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin