Year: 2020
Type: article
Abstract: We explore a class of primordial power spectra that can fit the observed anisotropies in the cosmic microwave background well and that predicts a value for the Hubble parameter consistent with the local measurement of H 0 = 74 km/s/Mpc. This class of primordial power spectrum consists of a continuous deformation between the best-fit power law primordial power spectrum and the primordial power spectrum derived from the modified Richardson-Lucy deconvolution algorithm applied to the C ℓ s of best-fit power law primordial power spectrum. We find that linear interpolation half-way between the power law and modified Richardson-Lucy power spectra fits the Planck data better than the best-fit ΛCDM by Δ log ℒ = 2.5. In effect, this class of deformations of the primordial power spectra offer a new dimension which is correlated with the Hubble parameter. This correlation causes the best-fit value for H 0 to shift and the uncertainty to expand to H 0 = 70.2 ± 1.2 km/s/Mpc. When considering the Planck dataset combined with the Cepheid H 0 measurement, the best-fit H 0 becomes H 0 = 71.8 ± 0.9 km/s/Mpc. We also compute a Bayes factor of log K = 5.7 in favor of the deformation model.
Authors: Ryan E. Keeley, Arman Shafieloo, Dhiraj Kumar Hazra, Tarun Souradeep
Institutions: Korea Astronomy and Space Science Institute, Korea University of Science and Technology, Istituto Nazionale di Fisica Nucleare, Sezione di Bologna, Osservatorio di Astrofisica e Scienza dello Spazio, Institute of Mathematical Sciences, National Institute for Astrophysics, Indian Institute of Science Education and Research Pune, Inter-University Centre for Astronomy and Astrophysics
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W3036622365