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arXiv · 2001.11689

Alleviating the Tension in the Cosmic Microwave Background using Planck-Scale Physics

Abhay Ashtekar·Brajesh Gupt·Donghui Jeong·V. Sreenath
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Abstract

Certain anomalies in the CMB bring out a tension between the six-parameter flat $Λ$CDM model and the CMB data. We revisit the PLANCK analysis with loop quantum cosmology (LQC) predictions and show that LQC alleviates both the large-scale power anomaly and the tension in the lensing amplitude. These differences arise because, in LQC, the primordial power spectrum is scale dependent for small $k$, with a specific power suppression. We conclude with a prediction of larger optical depth and power suppression in the $B$-mode polarization power spectrum on large scales.

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Abhay Ashtekar, Brajesh Gupt, Donghui Jeong, V. Sreenath. 2020-08-04. Alleviating the Tension in the Cosmic Microwave Background using Planck-Scale Physics. https://doi.org/10.1103/physrevlett.125.051302

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