Hidden parameters in the potentials of static fields

According to the classical potentials of Newton and Coulomb, a charged ball behaves as if all of its mass and all of its charge were concentrated at the centre. This simple picture is surely inadequate for the study of the behaviour of the field in the neighbourhood of the centre. The present paper aims at providing a new approach to this problem, particularly interesting for the microphysics, by means of the General Theory of Relativity. It is mainly concerned with establishing new solutions of Einstein's equations, which introduce new parameters (hidden parameters with respect to the classical model) associated with the spatial extension of the matter and the charges. Thus the obtained determination for the gravitational and electrostatic field allows us to get rid of the shortcomings of the classical scheme