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arXiv · 1506.00145

Two new tests to the distance duality relation with galaxy clusters

Abstract

The cosmic distance duality relation is a milestone of cosmology involving the luminosity and angular diameter distances. Any departure of the relation points to new physics or systematic errors in the observations, therefore tests of the relation are extremely important to build a consistent cosmological framework. Here, two new tests are proposed based on galaxy clusters observations (angular diameter distance and gas mass fraction) and $H(z)$ measurements. By applying Gaussian Processes, a non-parametric method, we are able to derive constraints on departures of the relation where no evidence of deviation is found in both methods, reinforcing the cosmological and astrophysical hypotheses adopted so far.

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S. Santos-da-Costa, V. C. Busti, R. F. L. Holanda. 2015-05-30. Two new tests to the distance duality relation with galaxy clusters. https://doi.org/10.1088/1475-7516%2F2015%2F10%2F061

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