|MadSci Network: Physics|
Our main point for this article is that one can regauge a potential, changing its local value, without necessarily changing the electric and magnetic fields (i.e., without changing the gradients of the potential). Or, one can regauge the potential asymmetrically and change the gradients, thereby obtaining a net free force field as well as free additional EM potential energy. Indeed, one can strongly argue that the passage of potential current d�/dt without passage of dq/dt is a regauging operation. The reason is that the Poynting flow S flows along an equipotential, which is another way of saying that a constant S-flow carries a constant orthogonal E-field and therefore a constant electrostatic scalar potential � value right along with it. It also carries a constant orthogonal B-field and therefore a constant magnetostatic scalar potential F value right along with it. In short, if one flows-in excess potential � or F, one has flowed-in excess S-flow. And vice-versa, if one flows-in excess S-flow, one has flowed-in excess potential, without necessarily changing the existing potential gradients (i.e., without changing the force fields).
This is in fact regauging, accomplished directly in the electric or magnetic circuit itself.
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