Hi. Different interpretations of QM have different opinions about the ontology of the wavefunction, i.e. if it really, physically exists or if it is "just" a mathematical tool needed to calculate the outcome of measurements. The QM interpretations comparison table on Wikipedia summarises the answer to this question in the "Wavefunction real?" column. So far I haven't seen similar discussions about the existence of classical fields, e.g. the electric field. It is defined at every point in space as the force that would act on a small charged test particle, divided by its charge. An analogous question now could be if the electric field really, physically exists in empty space or if it is only a mathematical tool. Is there a definite answer to this question? If not, in what way do the concepts "wavefunction" and "electric field" differ such that the question about existence seems to be much more debatable for the former?