  It is proposed a formalism of quantification of the electric charges in the
Kaluza Klein theory of five dimensions and a explanation of the cause of the
variation of the electromagnetic fine-structure constant in cosmological
times.There is a formalism that eliminates the problem that impeached the KK
theory to complete the unification of the electromagnetic and the gravitational
fields. The complete unification of these two fields is obtained. The radius of
compactation is determined as 70,238 lengths of Planck.
