Electric field inside conductor

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devd
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The common explanation for the electric field inside a conductor being zero goes something like this:

Suppose a perfect conductor is placed in an electric field, the external field causes the free charges to redistribute in such a way, that the resulting internal field exactly cancels off the external field, inside the body of the conductor.

I understand that a perfect conductor has unlimited supply of free electrons. But, my question is, how do i prove that there always exists a distribution of charges inside a conductor, which produces the internal electric field required to cancel off ANY external electric field. In other words, is it always possible to find such a distribution, for ANY external field, for ANY perfect conductor? How do i prove that?
 
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devd said:
n other words, is it always possible to find such a distribution, for ANY external field, for ANY perfect conductor? How do i prove that?
While this is possible (it is a special boundary value problem to find a charge distribution that leads to the correct electric potential), you can go the opposite way: Any field inside a conductor would lead to a current flow. There cannot be a current flow in equilibrium, and a conductor with a finite electric resistance will reach equilibrium.
 
devd said:
The common explanation for the electric field inside a conductor being zero goes something like this:

Suppose a perfect conductor is placed in an electric field, the external field causes the free charges to redistribute in such a way, that the resulting internal field exactly cancels off the external field, inside the body of the conductor.

I understand that a perfect conductor has unlimited supply of free electrons. But, my question is, how do i prove that there always exists a distribution of charges inside a conductor, which produces the internal electric field required to cancel off ANY external electric field. In other words, is it always possible to find such a distribution, for ANY external field, for ANY perfect conductor? How do i prove that?
http://en.wikipedia.org/wiki/Gauss's_law