The field of a positive charge Q on a spherical conductor is modeled by
continuous field lines which extend to infinity. This result is obtained
without regard to any assumptions about what is at infinity; it is simply
the result of the integration of Coulomb's law. One can assume either that
the charged sphere is the entire universe, or that it is infinitely removed
from the rest of the universe. The assumptions that the universe is neutral
and that field lines must terminate on a charge - and cannot simply go on
forever - are added, gratuitous assumptions (within Maxwellian theory) as
far as I can see. Can these assumptions be raised to the level of
corollaries to Maxwell's equations? I am willing to learn.
If you add a neighboring,oppositely charged sphere, at least one field line
will go off to infinity on one side and return from infinity on the other.
Bob Sciamanda (W3NLV)
Physics, Edinboro Univ of PA (em)
trebor@velocity.net
www.velocity.net/~trebor