Testing the "Dark-Energy"-Dominated Cosmology via the Solar-System Experiments

Abstract

The effect of "dark energy" (i.e. the Lambda-term in Einstein equations) is sought for at the interplanetary scales by comparing the rates of secular increase in the lunar orbit obtained by two different ways: (1) measured immediately by the laser ranging and (2) estimated independently from the deceleration of the Earth's proper rotation. The first quantity involves both the well-known effect of geophysical tides and the Kottler effect of Lambda-term (i.e. a kind of the "local" Hubble expansion), while the second quantity is associated only with the tidal influence. The difference between them, 2.2 +/- 0.3 cm/yr, can be attributed just to the local Hubble expansion with rate H_0^(loc) = 56 +/- 8 km/s/Mpc. Assuming that Hubble expansion is formed locally only by the uniformly distributed dark energy (Lambda-term), while globally also by a clumped substance (for the most part, the cold dark matter), the total (large-scale) Hubble constant should be H_0 = 65 +/- 9 km/s/Mpc. This is in reasonable agreement both with the commonly-accepted WMAP result, H_0 = 71 +/- 3.5 km/s/Mpc, and with the data on supernovae Ia distribution. The above coincidence can serve as one more argument in favor of the dark energy.