Information on the dynamical parameters of the Universe are coming from the Big Bang nucleosynthesis, from the fluctuations in the temperature and polarization of the cosmic microwave background radiation, from the large scale structures of galaxies, from supernova observations and from many other cosmological effects that may not yet be of interesting precision. The results of different analyses are now converging towards agreement when in the past disagreements of the order of 100% have been known.
In this review we have taken the attitude that remaining disagreements reflect systematic errors coming either from the observations or from differences in the methods of analysis. We have then compiled the most precise parameter values, combined them and added our estimates of such systematic errors. This we have done for the baryonic density parameter b h2, the density parameter of the matter component m, the density parameter of the cosmological constant , the spectral index of scalar fluctuations ns, the equation of state of the cosmological constant w, and the deceleration parameter q0. In addition we quote the best values of the Hubble parameter H0 and the total density parameter 0 from other sources. In Table 2 we summarize our results.
|H0||73 ± 7|||
|b h2||0.019 ± 0.002||our compilation|
|m||0.29 ± 0.06||our compilation|
|0.71 ± 0.07||our compilation|
|ns||1.02 ± 0.08||our compilation|
|w||< -0.86||our compilation|
|q0||-0.56 ± 0.04||our compilation|
The conclusion is not new: that the Universe is spatially flat, that some 25% of gravitating matter is dark and unknown, and that some 70% of the total energy content is dark, possibly in the form of a cosmological constant.
Acknowledgements: S. M. H. is indebted to the Magnus Ehrnrooth Foundation for support.