Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Topological properties of the Cosmic Microwave Background polarization
  map   Rapid progress has been made in observations of the temperature anisotropies
of the Cosmic Microwave Background (CMB). These observations have enabled
cosmologists to characterize the state of the universe at recombination, and
observational efforts are now being directed towards obtaining the polarization
map of the CMB. Here we draw an analogy between the CMB polarization map and
nematic liquid crystals, pointing out that the two have similar defects. Making
use of known results in the theory of defect formation we predict the
statistical distribution of defects in the CMB polarization map and provide a
novel tool for probing the CMB at large angular scales.

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The categories of this paper are: patt-sol
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The categories of this paper are: hep-lat
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The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
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The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
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The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph