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arXiv · 1310.2144

Constraining the Parameters of Modified Chaplygin Gas in Einstein-Aether Gravity

Ujjal Debnath
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Abstract

We have assumed FRW model of the universe in Einstein-Aether gravity filled with dark matter and Modified Chaplygin gas (MCG) type dark energy. We present the Hubble parameter in terms of some unknown parameters and observational parameters with the redshift z. From observed Hubble data (OHD) set (12 points), we have obtained the bounds of the arbitrary parameters (A,B) of MCG by minimizing the χ^{2} test. Next due to joint analysis of BAO and CMB observations, we have also obtained the best fit values and the bounds of the parameters (A,B) by fixing some other parameters. We have also taken type Ia supernovae data set (union 2 data set with 557 data points). Next due to joint analysis with SNe, we have obtained the best fit values of parameters. The best-fit values and bounds of the parameters are obtained by 66%, 90% and 99% confidence levels for OHD, OHD+BAO, OHD+BAO+CMB and OHD+BAO+CMB+SNe joint analysis. The distance modulus μ(z) against redshift z for our theoretical MCG model in Einstein-Aether gravity have been tested for the best fit values of the parameters and the observed SNe Ia union2 data sample.

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Ujjal Debnath. 2013-10-06. Constraining the Parameters of Modified Chaplygin Gas in Einstein-Aether Gravity. https://arxiv.org/abs/1310.2144

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