It is shown here, that relativistic shrinkage of the length of moving body is realizing strongly synchronously with the change of its velocity and is continuously self-sustaining without the effect of any forces. This shrinkage is caused by inertial isobaric self-contraction of body matter and by propagation of changes of the strengths of inertia forces field together with the front of body intrinsic time. A mechanism of kinetic energy filling (accumulation) of a body is considered and propagation of the phase waves of perturbation of gravitational field at supraluminal velocity is substantiated here.

It is shown that equations of the gravitational field of General Relativity should be considered just as equations of spatially inhomogeneous thermodynamic state of utterly cooled down matter. This matter can only be the hypothetical substances such as ideal gas, ideal liquid and the matter of absolutely solid body. The real matter will be inevitably cooling down for infinite time and never will reach the state that is described by the equations of gravitational field. Gravitational field itself is the field of spatial inhomogeneity of thermodynamic state of dense matter of compact astronomical objects, as well as of strongly rarefied gas-dust matter of space vacuum.