Both from gravitational (G) experiments and from a new theoretical approach based on a particle model it is proved that the classical invariability of the bodies, after a change of relative rest-position with respect to other bodies, it is not true. The same holds for the traditional hypotheses based on the classical one. The new relationships are strictly linear. From them it is proved that a universe expansion must be associated with a G expansion of every particle in it, in just the same proportion. It does not change the relative distances, indefinitely. From the relative viewpoint, globally, the universe must be rather static. According to the new cosmic scenario, galaxies must be evolving, indefinitely, in rather closed cycles between luminous and black states. The new kind of linear black hole must absorb radiation until it can explode after releasing new H gas that would trigger new luminous period of star clusters and galaxies. Statistically, most of the galaxies must be in cool states. The last ones should account for all of them, the higher velocities of the galaxies in clusters, the radiation coming from intergalactic space, including the low temperature black-body background observed in the CMBR.