As already investigated systematically in the author’s previous work "The Code of Nature", the values of the electron mass and the proton mass (me and mp) can be represented in a convincing manner by five physical constants plus a time-varying parameter. The five constants are the elementary electric charge e, the vacuum electric permittivity Єo, the Planck constant h, the speed of light c and the gravitational constant G. As a time-varying parameter, either the Hubble radius R or the Hubble constant H can be used. In the past few years it was the author’s intention to systematically derive and interpret the equation, which he discovered in 2012. Now the author has succeeded in elaborating a convincing derivation of the equation using the concept of matter waves. In addition, a highly symmetrical form of the equation was found by introducing four calculative masses based on physical constants.