ABSTRACT. The existence of the Hubble flow recession of galaxies in terms of dominance of dark energy density, vacuum energy, reduces the gravitational entropy of clusters of galaxies, reducing the gravitational entropy of the Universe as a whole. Global dominance of dark energy leads to a decrease in entropy of the Universe within the cosmic event horizon.Keywords: Hubble flow, movement of galaxies, clusters of galaxies, dark energy, entropy of the UniverseThe dominance of dark energy in the modern era leads to the dominance of anti-gravitation of gravity on cosmological scales. I.D.Karachentsev (Karachentsev & Kashlbadze, 2006;Karachentsev, 2005;Karachentsev et al., 2009;Karachentsev, Karachentseva & Huchtmeier, 2007) and A.D.Chernin (Chernin, Teerikorpi, Baryshev, 2003;Chernin et al., 2007;Chernin et al., 2009;Chernin et al., 2012;Chernin et al., 2013;Chernin et al., 2007;Chernin et al., 2012;Chernin, 2013;Teerikorpi & Chernin, 2010), studying the motions of galaxies in clusters, have shown that anti-gravity effects manifest themselves not only on a cosmic scale, but the scale of clusters of galaxies, for example -the Local Group, including our galaxy (the Milky Way) galaxy Andromeda and dozens of other smaller galaxies. M. Eingorn and A. Zhuk also studied in detail these issues (Brilenkov, Eingorn & Zhuk, 2015;Eingorn & Zhuk, 2012). Observations and modeling have shown that at distances of 1-3 Mpc from the center of the gravity bounded Local Group of galaxies it is observed the local flow of divergent dwarf galaxies. The velocities of these galaxies are proportional to the distance from the center. A.D. Chernin et al. (2012) have shown that such flows, which are observed in other clusters at different scales, form under the influence of dark energy. So, for Local Groups zone of zero gravity in which the gravitational force is balanced by the force of attraction and anti-gravitation is the R ZG ≈1.3÷1.4 Mpc. Therefore, when R>R ZG the flow of recession of galaxies starts. A.D.Chernin and colleagues studied the behavior of galaxies streams, build charts based on experimental data and numerical simulation and showed that the phase trajectories of the local stream tend to phase attractor V=H x R, that corresponds to the Hubble law. In this case H x =(8πGρ x /3) 1/2 is determined by the local density of dark energy (Chernin, 2013). Therefore, when R>R ZG flow of receding galaxies starts. In this case the phase trajectories of the local flow tend to phase attractor V=H x R, that is, obey the Hubble law. From experimental diagram of velocities of galaxies we can estimate that the spread of own velocities of galaxies with R R ZG velocity spread to the theoretical velocity of Hubble divergence flow averages about ΔV= 12 km/s (Bukalov, 2014). Antigravity of dark energy, or the energy of the vacuum, reduces the dispersion of velocity galaxies. The difference in entropy in areas with R < R ZG and R > R ZG is negative, so "evaporation" of the ga...