Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Existence results for the Klein-Gordon-Maxwell equations in higher
  dimensions with critical exponents   In this paper we study the existence of radially symmetric solitary waves in
R^N for the nonlinear Klein-Gordon equations coupled with the Maxwell's
equations when the nonlinearity exhibits critical growth. The main feature of
this kind of problem is the lack of compactness arising in connection with the
use of variational methods.

18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an
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The categories of this paper are: atom-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: eess
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
36
The categories of this paper are: cmp-lg
6
The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg