Structure of the wiffleball plasma.

[KeithChard]

We seem to have a good idea of the structure of the E and B fields outwith the wiffleball, but what about the structure inside? I hope we can build an understanding of the structure of these fields in the plasma or in the skin because it is possible that this structure provides an additional mechanism for retaining the electrons.

I am told that there are no magnetic fields inside the wiffleball because the plasma is a superconductor and therefore, by analogy with the Meissner effect, all magnetic field is expelled. I am not completely convinced, because the geometry of a wire that can carry a single current between it's ends, or any other geometry which can support a single coherent current, is very different from our plasma which is contained by a multiple combination of magnetic and electric fields. If the bulk of the plasma is to be free of magnetic field, what is the structure of the currents and fields in the outer layers of the plasma? It would have to be a system tailored to repelling the field from each of the Magrid magnets, would it not? That returns us to the arrangement given by the method of images, but possibly squashed up into the skin of the wiffleball. That poses the question of why the field lines of the image magnets should not penetrate towards the centre of the wiffleball.

The alternative explanation for a plasma free of magnetic field is one I also find difficult to understand, because the creation of back e.m.f. requires a coherent current in the plasma, whereas we have electrons bouncing about but, aside from start-up currents and loss currents, no coherent net current, unless we have a system of image currents, as above. Has the virtual Polywell advanced far enough to give some clues to the answers?