Determination of the dynamical parameters of the Universe and its age

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We determine the density parameters Ωₘ of gravitating matter and ΩΛ of vacuum energy, by making a χ² fit to nine independent astrophysical constraints. Paying rigorous attention to statistical detail, we find that the present best values are Ωₘ=0.31± 0.07, ΩΛ=0.70± 0.13, where these 1σ errors are approximately Gaussian (thus trivially convertible to whatever percentage confidence range desired). The total χ² is 2.5 for 7 degrees of freedom, testifying that the various systematic errors included are generous. Since Ωₘ + ΩΛ= 1.01± 0.15, it follows that the Einstein-de Sitter model is very strongly ruled out, that also any low-density model with ΩΛ=0 is ruled out, and that a flat cosmology is not only possible, but clearly preferred. In the flat case we find Ωₘ=0.31± 0.04, from which it follows that the age of the Universe is t₀ = 13.7⁺¹.²₋₁.₁(0.68/h) Gyr.