Alleviation of anomalies from the nonoscillatory vacuum in loop quantum cosmology

Abstract

In this work, we investigate observational signatures of a primordial power spectrum with exponential infrared suppression, motivated by the choice of a nonoscillatory vacuum in a bouncing and inflationary geometry within loop quantum cosmology. We leave the parameter that defines the scale at which suppression occurs free and perform a Bayesian analysis, comparing with cosmic microwave background data. The data show a preference for some of the suppression to be within the observable window. Guided by this analysis, we choose concrete illustrative values for this parameter. We show that the model affects only slightly the parity anomaly, but it is capable of alleviating the lensing and power suppression anomalies.