$\star$ Probes of black energy and future...

Current measurements indicate that $\rightarrow$ 2. In this range of redshift, the flood of Hubble is largely reached. Moreover, this range of redshift makes it possible to trace the evolution of the density of black energy over all the period when it prevails. Beyond 2, the matter becomes dominant and determines the expansion. Lastly, the evolution according to the shift towards the red could make it possible to measure a possible evolution of the equation of state .

Measurements of the anisotropies of the cosmological diffuse bottom have a limited capacity, measurements which could be made by the satellite dedicated Planck will be able as well as possible to reach precise details of about 10%. Moreover, these measurements have only one lever limited in spectral shift, and will not be able to make of differential measurement of $\sigma_\omega = 0.05$ by considering an intrinsic uncertainty of the luminosity of 14% (aldering2002). Moreover, if one manages to measure indépendemment $\sigma_{\omega' }$ of 0.16.

Figure 1.10: Contour of confidence in the plan $(\Omega _ { \rm M}, \omega _ X)$ awaited by the satellite SNAP which should observe 2000 supernovæ per annum during 3 years with redshifts ranging between 0.1 and 1.7.

The methods of counting of galaxies and cluster have the same precision potentially as the supernovæ of the type Ia. Cependant, with many problems the systematic ones sully this type of measurement and measurements strongly depend on the models considered.

Lastly, the measurement of the effects of lenses weak on a surface of $\omega$ (huterer2002).