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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 Omegab h2, the density parameter of the matter component Omegam, the density parameter of the cosmological constant Omegalambda, the spectral index of scalar fluctuations ns, the equation of state of the cosmological constant wlambda, and the deceleration parameter q0. In addition we quote the best values of the Hubble parameter H0 and the total density parameter Omega0 from other sources. In Table 2 we summarize our results.

Table 2. Best values of the dynamical parameters. The errors include 1sigma statistical errors and our estimates of systematic errors, except for Omega0 which is statistical only. The Hubble constant H0 is given in units of km s-1 Mpc-1

Parameters Values References

H0 73 ± 7 [9]
Omegab h2 0.019 ± 0.002 our compilation
Omegam 0.29 ± 0.06 our compilation
Omegalambda 0.71 ± 0.07 our compilation
Omega0 1.0 +0.03-0.02 [43]
ns 1.02 ± 0.08 our compilation
wlambda < -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.

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