It strikes me as analogous to the near and far field of a radio antenna? The complicated initial close-in chaos corresponds to the complicated near field of an

It strikes me as analogous to the near and far field of a radio antenna? The complicated initial close-in chaos corresponds to the complicated near field of an antenna. As the EM wave propagates further away from the antenna it assumes a simpler "far field" structure. On other words, as the wave gets further away from the antenna the physical extent of the antenna becomes neligible compared to the distance propagated, so the field looks more and more like that from a simpler point source.