Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Anisotropic effects of background fields on Born-Infeld electromagnetic
  waves   We show exact solutions of Born-Infeld theory for electromagnetic plane waves
propagating in the presence of static background fields. The non-linear
character of Born-Infeld equations generates an interaction between background
and wave that changes the speed of propagation and adds a longitudinal
component to the wave. As a consequence, in a magnetic background the ray
direction differs from the propagation direction --a behavior resembling the
one of a wave in an anisotropic medium--. This feature could open up a way to
experimental tests of Born-Infeld theory.

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The categories of this paper are: adap-org
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The categories of this paper are: eess
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
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The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
37
The categories of this paper are: supr-con
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
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The categories of this paper are: alg-geom
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The categories of this paper are: chao-dyn
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The categories of this paper are: nlin
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The categories of this paper are: econ
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat