Informational approach to cosmological parameter estimation
Abstract
We introduce a new approach for cosmological parameter estimation based on the information-theoretical Jensen-Shannon divergence (DJS), calculating it for models in the restricted parameter space {H0,w0,wa}, where H0 is the value of the Hubble constant today, and w0 and wa are dark energy parameters, with the other parameters held fixed at their best-fit values from the Planck 2018 data. As an application, we investigate the H0 tension between the Planck temperature power spectrum data (TT) and the local astronomical data by comparing the Λ CDM model with the w CDM and the w0waCDM dynamic dark energy models. We find agreement with other works using the standard Bayesian inference for parameter estimation; in addition, we show that while the DJS is equally minimized for both values of H0 along the (w0,wa) plane, the lines of degeneracy are different for each value of H0. This allows for distinguishing between the two, once the value of either w0 or wa is known.
- Publication:
-
Physical Review D
- Pub Date:
- December 2020
- DOI:
- 10.1103/PhysRevD.102.123514
- arXiv:
- arXiv:1905.07472
- Bibcode:
- 2020PhRvD.102l3514S
- Keywords:
-
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- High Energy Physics - Phenomenology
- E-Print:
- 5 pages, 3 figures. Final version accepted for publication in Physical Review D. Includes a new error analysis, a new figure, additional references, and a new author