>>How would you measure a voltage without having any current flowing --
>>i.e. without relocating some charge carriers?
>
> You can't without relocating any charge carriers, so why not relocate some
> and put them back immediately ? Like in a vibrating reed voltmeter/charge
> meter. You have a moving electrode in an electrical field. The motion is
> repetitive and the probe will sense an ac voltage with amplitude equal to
> the difference in potential between the two extremes of the motion. It
> need not touch anything. The energy comes from the mechanism that does the
> moving, by moving the probe charge in the field. A small influence will be
> sensed on the measured object but it will be ac. The electrophorus
> operates on the same principle.

That's a good trick. But you would agree with me that you are measuring
resistance at a current > 0A? One of the questions debated was whether
there is a resistance (or whether it makes sense to speak of one) if there
is no current flowing. In your experiment, current is flowing, forth and
back, if I understand it correctly.

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