The distance-redshift equation in quintessence cosmology and the estimation of H0 through time delays

• Verfasst von: Giovi, Fabio [VerfasserIn]
• Verfasst von: Amendola, Luca [VerfasserIn]
• Titel: The distance-redshift equation in quintessence cosmology and the estimation of H0 through time delays
• Verf.angabe: Fabio Giovi, Luca Amendola, Osservatorio Astronomico di Roma, Viale del Parco Mellini 84, 00136 Roma, Italy
• Umfang: 12 S.
• Fussnoten: Im Titel ist „0“ tiefgestellt ; Gesehen am 17.11.2017
• Titel Quelle: Enthalten in: Royal Astronomical Society: Monthly notices of the Royal Astronomical Society
• Jahr Quelle: 2001
• Band/Heft Quelle: 325(2001), 3, S. 1097-1108
• ISSN Quelle: 1365-2966
• DOI: doi:10.1046/j.1365-8711.2001.04531.x
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 156545538X

Abstract

We calculate analytically and numerically the distance-redshift equation in perfect fluid quintessence models and give an accurate fit to the numerical solutions for all the values of the density parameter and the quintessence equation of state. Then we apply our solutions to the estimation of H0 from multiple image time delays and find that the inclusion of quintessence modifies significantly the likelihood distribution of H0, generally reducing the best estimate with respect to a pure cosmological constant. Marginalizing over the other parameters (Ωm and the quintessence equation of state) we obtain H0=71±6 km s−1 Mpc−1 for an empty beam and H0=64±4 km s−1 Mpc−1 for a filled beam. These errors, however, do not take into account the uncertainty on the modelling of the lens. We also discuss the future prospects for distinguishing quintessence from a cosmological constant with time delays.