so, the name "longitudinal electric waves" turns most people who think they know anything about electricity off...usually automatically. officially, em only applies for transversally (however that becomes a nuanced conversation when you start to involve waveguides that utilize tm and te modes of propagation).  anyway, telluric currents are related to this. so is magnetic resonant coupling.  single wire electricity (no earth return) is a real, experimentally verifiable thing though, and this vid shows one of the experiments.    2hg9aryo
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