Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Stability Analysis of New Solutions of the EYM system with Cosmological
  Constant   We analyze the stability properties of the purely magnetic, static solutions
to the Einstein--Yang--Mills equations with cosmological constant. It is shown
that all three classes of solutions found in a recent study are unstable under
spherical perturbations. Specifically, we argue that the configurations have
$n$ unstable modes in each parity sector, where $n$ is the number of nodes of
the magnetic Yang--Mills amplitude of the background solution. The
``sphaleron--like'' instabilities (odd parity modes) decouple from the
gravitational perturbations. They are obtained from a regular Schr\"odinger
equation after a supersymmetric transformation. The body of the work is devoted
to the fluctuations with even parity. The main difficulty arises because the
Schwarzschild gauge -- which is usually imposed to eliminate the gravitational
perturbations from the Yang--Mills equation -- is not regular for solutions
with compact spatial topology. In order to overcome this problem, we derive a
gauge invariant formalism by virtue of which the unphysical (gauge) modes can
be isolated.

0
The categories of this paper are: hep-ph
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The categories of this paper are: cs
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph