Charge densities that change linearly with time are effectively electrostatic

Edward Parker

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arXiv · 1708.05060

Charge densities that change linearly with time are effectively electrostatic

Edward Parker

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Abstract

We consider classical electromagnetic systems in which the current density ${\bf J}$ does not change with time, but has nonzero divergence, so that electric charge does build up steadily over time. We show that for such a system, the \emph{exact} electromagnetic fields are given by the Coulomb and Biot-Savart laws with the sources evaluated at the \emph{present} (rather than retarded) time, even though the charge density is changing over time.

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Edward Parker. 2017-07-18. Charge densities that change linearly with time are effectively electrostatic. https://arxiv.org/abs/1708.05060

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