Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observational cosmology and the cosmic distance-duality relation   We study the validity of cosmic distance duality relation between angular
diameter and luminosity distances. To test this duality relation we use the
latest Union2 Supernovae Type Ia (SNe Ia) data for estimating the luminosity
distance. The estimation of angular diameter distance comes from the samples of
galaxy clusters (real and mock) and FRIIb radio galaxies. We parameterize the
distance duality relation as a function of redshift in four different ways and
we find that the mock data set, which assumes a spherical isothermal $\beta$
model for the galaxy clusters does not accommodate the distance duality
relation while the real data set which assumes elliptical $\beta$ model does.

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The categories of this paper are: chao-dyn
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The categories of this paper are: nlin
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
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The categories of this paper are: q-alg
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The categories of this paper are: bayes-an
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The categories of this paper are: patt-sol
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The categories of this paper are: math-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: comp-gas
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The categories of this paper are: solv-int
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The categories of this paper are: eess
0
The categories of this paper are: hep-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: stat
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The categories of this paper are: hep-th