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

Abstract

Certain anomalies in the CMB bring out a tension between the six-parameter flat ΛCDM 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. © 2020 American Physical Society.