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Attempt at evaluating the potential for an infinite cylinder.\
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 "\n\nEvaluating this appears non-trivial, especially if we let L tend to \
infinity.  Note that the  integral in the z component \
doesn\[CloseCurlyQuote]t converge if we let the L go unbounded, even if we \
take the principle value of the integral.\n\nGoogling this problem, I find:\n\
\nhttp://www.ifi.unicamp.br/~assis/J-Electrostatics-V63-p1115-1131(2005).pdf\n\
\ndecidedly non-trivial!  It would take a couple of years of study to even \
try to read that paper.\n"
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