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arXiv · 1212.6612

Testing cosmic opacity from SNe Ia and Hubble parameter through three cosmological-model-independent methods

Kai Liao·Zhengxiang Li·Jing Ming·Zong-Hong Zhu
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Abstract

We use the newly published 28 observational Hubble parameter data ($H(z)$) and current largest SNe Ia samples (Union2.1) to test whether the universe is transparent. Three cosmological-model-independent methods (nearby SNe Ia method, interpolation method and smoothing method) are proposed through comparing opacity-free distance modulus from Hubble parameter data and opacity-dependent distance modulus from SNe Ia . Two parameterizations, $τ(z)=2εz$ and $τ(z)=(1+z)^{2ε}-1$ are adopted for the optical depth associated to the cosmic absorption. We find that the results are not sensitive to the methods and parameterizations. Our results support a transparent universe.

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Kai Liao, Zhengxiang Li, Jing Ming, Zong-Hong Zhu. 2012-12-29. Testing cosmic opacity from SNe Ia and Hubble parameter through three cosmological-model-independent methods. https://doi.org/10.1016/j.physletb.2012.12.022

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