Potential theory and the Lorenz condition

When potentials are used to calculate the electromagnetic field intensities choices may be made. The present study is carried out in order to outline the various possibilities. It looks like the types of choices and their number depend on the actual situation and the preferences of the researcher. Also the explanations as to why choices can be made vary. Since potentials probably are more basic than field intensities, it is of some interest to understand whether choices can be related to physical interpretations or computational advantages in specific situations. In particular, it is discussed whether the Lorenz condition is a choice or a consequence. It turns out that facts in relation to potentials depend on the postulates made