found by a heuristic method, is also of great importance. Now the rest mass of a charged particle (if we are consequent and consider E_w Ew as a result of an orbital rule) appears as a variable quantity since firstly this is certainly not the only orbital rule, and since secondly we do not want to doubt the speed of light to be a universal constant. And really, there is a relationship – similar to the Sommerfeld fine structure constant (that increased our doubt about the universality of h) – that seems to suggest that this idea is not absurd: the constant ratio of the rest masses of electron and proton. Should this ratio perhaps be the result of two orbital rules of one and the same particle, only with different polarity signs? We will not shrink back from such an idea because anyway we must be aware that our causal approach – while it claims to achieve more than quantum theory – is also able to explain the nucleus. Still a second train of thought leads to the full justification of this question:
until now we have studied the self-interaction of an electron that was forced by the Coulomb attraction to stay on a predefined spherical shell or on the surface of an ellipsoid. Thus, this self-interaction is “not free”. Therefore, we have every right to ask: what will happen if we liberate the electron from this fetter so that it can interact with itself – being totally free? Such a mechanism should be found if we consequently continue to adopt the method we have used thus far. We can also examine the guessed approach E_w = m_oc² from a third, most interesting point of view:
It has already become common praxis in nuclear physics that masses are converted into energies, and vice versa. Thus, the rest mass of a particle (in the old traditional concept as a “matter clot”) has lost its conceptual basis long ago and appears as compressed energy. This is not surprising at all because long since there have been a lot of aspects that support the idea that the atomic nucleus (similar to the shell) is empty, too. For example, the “non-nucleus” particles can pass through many nuclei without interaction. From this view, the approach:

is the key to the physical understanding of the Einstein mass-energy ratio and we formulate: