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arXiv · 0910.5835

Constraints on Cardassian universe from Gamma ray bursts

Tai-Shan Wang·Nan Liang
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Abstract

Constraints on the original Cardassian model and the modified polytropic Cardassian model are examined from the recently derived 42 gamma-ray bursts (GRBs) data calibrated with the method avoiding the circularity problem. The results show that GRBs can be an optional observation to constrain on the Cardassian models. Combining the GRBs data with the newly derived size of baryonic acoustic oscillation peak from the Sloan Digital Sky Survey (SDSS), and the position of first acoustic peak of the Cosmic Microwave Background radiation (CMB) from Wilkinson Microwave Anisotropy Probe (WMAP), we find $\Omega_{m0}=0.27_{-0.02}^{+0.02}, n=0.06_{-0.08}^{+0.07}$ ($1\sigma$) for the original Cardassian model, and $\Omega_{m0}=0.27^{+0.03}_{-0.02}$, $n=-0.09_{-1.91}^{+0.23}, \beta=0.82_{-0.62}^{+2.10}$ ($1\sigma$) for the modified polytropic Cardassian model.

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Tai-Shan Wang, Nan Liang. 2009-10-30. Constraints on Cardassian universe from Gamma ray bursts. https://doi.org/10.1007/s11433-010-4100-4

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