Pugh, E. M.
Text: "Physical significance of the Poynting vector in static fields." Deals with divergence-free energy flows. A permanent magnet placed in a static electric field exhibits non-zero values for the Poynting vector, which means energy is flowing in closed paths with zero divergence. In the scalar electromagnetic view, the static field increases the total charge of vacuum in the system, resulting in a flow of anenergy between the higher charged vacuum region and the surrounding ambient vacuum. Since this flow is virtual and massless, macroscopically it is the same as energy flowing in closed paths with zero divergence. At any rate, if this anenergy flow can be tapped, one can utilize it to produce free energy, since the system is locally a general relativistic system and energy need not be conserved. In other words, one can put a "subtle paddlewheel" in this "subtle river" and extract usable energy. American Journal of Physics. 35, 1967. p. 153-156.
See Also: foundations of physics, Poynting vector, static fields, scalar electromagnetics.
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