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arXiv · 1806.11425

Finsler space-time can explain both parity asymmetry and power deficit seen in CMB temperature anisotropies

Zhe Chang·Pranati K. Rath·Yu Sang·Dong Zhao·Yong Zhou
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Abstract

We propose a framework of Finsler space-time to explain the observed parity asymmetry and the power deficit in the low-$\ell$ ($2\leqslant \ell \leqslant 29$) multipole range of cosmic microwave background (CMB) temperature anisotropies. In the $3+1$ dimensional space-time, the three-dimensional space is described by a Randers-Finsler space, which is spatially irreversible, inducing the parity asymmetry in the CMB angular power spectrum. We estimate the constraints on the two parameters introduced by Finsler space-time via analyzing the low-$\ell$ angular power spectrum in PLANCK 2015 CMB temperature data. We see that the low-$\ell$ power suppression in the CMB temperature anisotropies can also be resolved in this scenario. Our study shows that the two low-$\ell$ anomalies, i.e., parity asymmetry and power deficit, may have a common origin.

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Zhe Chang, Pranati K. Rath, Yu Sang, Dong Zhao, Yong Zhou. 2018-06-29. Finsler space-time can explain both parity asymmetry and power deficit seen in CMB temperature anisotropies. https://doi.org/10.1093/mnras%2Fsty1689

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