Determination of the dynamical parameters of the Universe and its age

dc.creatorRoos, Matts
dc.creatorHarun-or-Rashid, S. M.
dc.date1999-01-18
dc.date1999-12-07
dc.date.accessioned2026-07-07T02:30:02Z
dc.date.available2026-07-07T02:30:02Z
dc.descriptionWe determine the density parameters $Ω_m$ of gravitating matter and $Ω_Λ$ of vacuum energy, by making a $χ^2$ fit to nine independent astrophysical constraints. Paying rigorous attention to statistical detail, we find that the present best values are $Ω_m=0.31\pm 0.07, Ω_Λ=0.70\pm 0.13$, where these $1σ$ errors are approximately Gaussian (thus trivially convertible to whatever percentage confidence range desired). The total $χ^2$ is 2.5 for 7 degrees of freedom, testifying that the various systematic errors included are generous. Since $Ω_m + Ω_Λ= 1.01\pm 0.15$, it follows that the Einstein-de Sitter model is very strongly ruled out, that also any low-density model with $Ω_Λ=0$ is ruled out, and that a flat cosmology is not only possible, but clearly preferred. In the flat case we find $Ω_m=0.31\pm 0.04$, from which it follows that the age of the Universe is $t_0 = 13.7^{+1.2}_{-1.1}(0.68/h)$ Gyr.
dc.description17 Pages, 1 Figure, LaTeX2e
dc.identifierhttps://arxiv.org/abs/astro-ph/9901234
dc.identifierhttp://arxiv.org/abs/astro-ph/9901234
dc.identifierEPS-HEP'99 proceedings (IoP Publishing 2000)
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/13700
dc.subjectAstrophysics
dc.titleDetermination of the dynamical parameters of the Universe and its age
dc.typetext

Files

Collections