The gravitation in a flat space

It is shown that the theory of gravitational field can be and has to be built in a flat space defined, in the case of Einstein's theory, by Fock's harmonic coordinates. The gravitational metric tensor is only a quantity describing the interaction of this field with other matter. The field reduces the rest energy of the other matter and contracts its size, causing thus gravitational red shift and incorrectness of determination of distance with a meter-stick.The energy of the gravitational field should be positive and localizable and its density should be given by the Einstein energy-momentum quasitensor; the conclusion of its negativity had been arrived at due to an incorrect evaluation of its exchange by work. A correct generalization of the relation between these two quantities in the presence of a gravitational field is made. The role of harmonic coordinates as the Minkowski coordinates of real space-time is justified by the weak-field limit. The results are applied to dynamically explain the special theory of relativity. (author)