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arXiv · 1801.02773

Anisotropic power spectrum and the observed low-l power in PLANCK CMB data

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

In this work, we study a direction dependent power spectrum in anisotropic Finsler space-time. We use this direction dependent power spectrum to address the low-l power observed in WMAP and PLANCK data. The angular power spectrum of the temperature fluctuations has a lower amplitude in comparison to the $\Lambda$CDM model in the multipole range l = 2-40. Our theoretical model gives a correction to the isotropic angular power spectrum $C^{TT}_l$ due to the breaking of the rotational invariance of the primordial power spectrum. We estimate best-fit model parameters along with the six $\Lambda$CDM cosmological parameters using PLANCK likelihood code in CosmoMC software. We see that this modified angular power spectrum fits the CMB temperature data in the multipole range l=2-10 to a good extent but fails for the whole multipole range l = 2-40.

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Zhe Chang, Pranati K. Rath, Yu Sang, Dong Zhao. 2018-01-09. Anisotropic power spectrum and the observed low-l power in PLANCK CMB data. https://doi.org/10.1088/1674-4527/18/3/29

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