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The Lienard-Wiechert retarded solution to Maxwell's equations has the radiation fields diverging and propagating away from an accelerating charge; the advanced solution has radiation fields converging onto the charge.

Obviously an accelerating charge can generate the retarded EM radiation, but does there exist a charge distribution able to generate the advanced EM radiation converging to a point?

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In macroscopic EM theory, such phenomenon is extremely unlikely, as the reports of its observations are few and fringe. Theoretically it means distant EM field in every direction now is correlated with the localized charge distribution motion in the future, which is hard to accept for its acausal description of EM field (EM field could no longer be thought of as created by the charge distribution).

The EM field could manifest a component of advanced character if such "acausal" correlation was caused by experimenter, for example by putting a spherical reflector around the charge distribution - then there would be an incoming wave collapsing on the charge distribution - but it would be only a part of the total EM field, not all of it.

In microscopic EM theory, we do not know - there are attempts to explain macroscopic EM phenomena as a result of microscopic fields that contain but aren't equal to advanced fields (action at a distance theories of Tetrode, Fokker, Frenkel, Feynamn-Wheeler). But these attempts to use advanced fields to advance our understanding of EM phenomena had limited success.

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  • $\begingroup$ I didn't make myself clear so I've edited the question: converging to a point rather than at the charge's position which your second paragraph answers. $\endgroup$ – Larry Harson Mar 8 at 0:34
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The advanced solution has radiation fields diverging and propagating away from an accelerating charge too. The problem is that human beings are experiencing outgoing advanced waves (traveling backwards in time) as incoming waves (traveling forward in time) and converging to a point, as explained in this paper: https://www.researchgate.net/publication/320163131_The_hidden_arrow_of_electromagnetic_radiation_unmasking_advanced_waves

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