Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Preliminary Preparations: Scattering Problem of Double-layered Sphere
  Containing Left-handed Media   In this paper, we present Mie coefficients of double-layered sphere and
consider the scattering problem, including the topics on field distribution,
electromagnetic cross section, extinction spectra as well as some potential
peculiar properties arising from the presence of left-handed media. The
formulation presented here can be easily generalized to cases of
multiple-layered spheres.

10
The categories of this paper are: q-bio
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The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
21
The categories of this paper are: adap-org
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
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The categories of this paper are: eess
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The categories of this paper are: alg-geom
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The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math