Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Regularized Transformation-Optics Cloaking in Acoustic and
  Electromagnetic Scattering   We consider transformation-optics based cloaking in acoustic and
electromagnetic scattering. The blueprints for an ideal cloak use singular
acoustic and electromagnetic materials, posing server difficulties to both
theoretical analysis and practical fabrication. In order to avoid the singular
structures, various regularized approximate cloaking schemes have been
developed. We survey these developments in this paper. We also propose some
challenging issues for further investigation.

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The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
24
The categories of this paper are: dg-ga