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arXiv · 1405.3074

Constraining the Anisotropy of the Universe from Supernovae and Gamma-ray Bursts

Zhe Chang·Xin Li·Hai-Nan Lin·Sai Wang
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Abstract

Recently, an anisotropic cosmological model was proposed. An arbitrary 1-form, which picks out a privileged axis in the universe, was added to the Friedmann-Robertson-Walker line element. The distance-redshift relation was modified such that it is direction dependent. In this paper, we use the Union2 dataset and 59 high-redshift gamma-ray bursts to give constraints on the anisotropy of the universe. The results show that the magnitude of anisotropy is about $D=-0.044\pm0.018$, and the privileged axis points towards the direction $(l_0,b_0)=(306.1^{\circ}\pm 18.7^{\circ},-18.2^{\circ}\pm 11.2^{\circ})$ in the galactic coordinate system. The anisotropy is small and the isotropic cosmological model is an excellent approximation.

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Zhe Chang, Xin Li, Hai-Nan Lin, Sai Wang. 2014-05-13. Constraining the Anisotropy of the Universe from Supernovae and Gamma-ray Bursts. https://doi.org/10.1142/s0217732314500679

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