We will study a so-called radial gravitational wave corresponding to a wave which is not diffused in all directions, but in a single direction. We will establish that its energy level depends, in the same way as an electromagnetic radiation, of its amplitude (constant over all its trajectory), correlated then to its electric field, and of the discrete potential of energy, then given by its frequency multiplied by the Planck constant. We will then observe the structure of the wave, corresponding to a series of contractions and dilations of space. This will describe the discrete nature of the radiation and provide a beginning of response to the paradox of increasing mass, directly derived from General Relativity. By considering the quantity of energy of the radial wave and in application of the Special Relativity, we will note its contraction which will make it possible to explain the observed corpuscular aspect of the radiation. It will thus be determined that an electromagnetic radiation, then identified as a radial gravitational wave, is in reality neither exclusively a wave nor actually a corpuscle, these notions not being dissociable here, but as a radial wave whose space, in which the quantity of energy is distributed, is, from the point of view of an external observer, infinitely contracted. The "problem" of the wave-particle duality will then be solved in the case of electromagnetic radiations, ie relativistic particles (of zero mass), whose discrete nature will be determined, a physical meaning will be given to the constant of fine-structure, the electric field will then be described as a property of Space-Time (more than a force field), and a quantization start of Space-Time compatible to the observation will be provided.