On it site the relativist theory of a field is shown, according to which any space containing gravitationally or electrically charged substance, is limit and closed. On the basis of classical representations of the special theory of a relativity, the ratio connecting scale spatio-temporal continuum to a charge of a gravitational or an electrical nature is received. Is shown, that gravitationally or electrically the charged substance a positive or negative mark in absence of external potential forms closed space - time appropriate  nature, and density spatio-temporal continuum in each point is determined by size etherformative of a charge in all closed volume. The interrelation of space, time both matter as charges and fields, connection between scale unified spatio-temporal continuum and physical condition of substance is established. The new theory shows the gear of expansion of closed space -  time. The equations of the unified field theory determining law of mutual transformation of electrical, magnetic and gravitational fields are received.