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Joel Rauber, being dissatisfied with the idea of charges at infinity,wrote:
I have never been happy with the statement that the field lines on the +Q
charge must continue to -Q's at infinity. . . . .
Whether or not the idea of a universe with a net electric charge is a. . .
necessity or just a convenience depends on the asymptotic topological
structure of the spatial sections of the spacetime of the universe. If the
universe is spatially infinite then the idea of neutralizing charges at
infinity is a convenience. If the universe is topologically compact, (i.e.
closed and bounded in extent) then the universe *must* be charge-neutral.
If one writes the Poisson equation for the potential on a compact spacewith
a net nonzero source charge (i.e. integral of the charge density over the
entire space) the equation will admit no solution. If the whole compact
space is charge-neutral, however, the solution is unique up to an arbitrary
additive constant.
BTW, I don't mind at all saying that a capacitor is charged and discharged.the
I *do* believe, however, that before ever using the word 'charge' as a verb
in connection with a capacitor, that the instructor very carefully define
the meaning of that verb in terms of a process where net positive charge
accumulates on one electrode 'plate' via conduction from a connection to an
external circuit *and* a compensating net negative charge accumulates on
other electrode 'plate' via conduction to the other side of the external
circuit in such a way that the total net charge on both electrode plates
together remains effectively zero.