The idea that a mass is the source of a basic field \(\Xi\) of the universe is introduced. It is called Space-Time Field because it builds both the Space-Time and the particles in it, using an original formulation of quantum oscillator (IQuO). This field is fed with energy flowing from a background (Θ) having the structure of no-field because it is composed by no-coupled IQuO. Note that the mass creation has a double consequence: gravity increase (curvature) and space increase (expansion). This allows to formulate a universe model with a variable metric (open in the past, flat in the present and closed in the future) and to explain some fundamental aspects of the universe: the Hubble’s law by creating the mass-space, the acceleration of galaxies as effect of a pressure of increasing Space-Mass \(\Lambda\), the age of the universe as time needed to reach the flat metric phase.