Art wrote:
"Frank, It has not yet been proven that current does not flow through
the center of the radiator."

It definitely has been proven that significant current does not
ordinarily flow through the center of a radiating conductor.

Skin effect is an accepted and observed phenomenon.

An RF conductor has a radial E-field, its lines terminating on its
surface. Also, the current carrying conductor has has an H-field whose
lines encircle it. The E-field lines are not exactly
perpendicular to to the conductor`s surface but inclined at a slight
angle to it. The surfaces of equal phase are cupped inward slightly on
the forward side as if the wave were dragging its feet along the
conductor`s surface. The H lines are parallel to the conductor`s
surface. Direction of propagation of the energy is at right angles to
both the E and H fields, but not quite parallel to the conductor`s
surface. It is inclined slightly toward the inside of the conductor.
Direction of propagation can be indicated by a vector P. P can be
resolved into two components, PL and PR . PL represents the longitudinal
component of vector P. PR represents the small amount of energy which is
being drained away from the transmitted signal and dissipated as heat in
the conductor. Radial E lines of force tilted forward in propagation
along the conductor are slowed and short-circuited by the conducting
material through which they are moving. This current flowing through the
resistance of the conductor causes I squared R losses. It also gives
rise to a magnetic field within the conductor which opposes the external
H field.

The result of the above is that the density of the current is quite high
at the copnductor`s surface, diminishing as we look inward toward the
center. The relative phase of the current, in addition, is not the same
at all depths; because of the slow velocity of propagation of the wave
within the conductor, the phase of the current is progressively delayed
as we examine it at greater depths. At some depth, the phase of the
current may be 180 degrees behind that of the surface current, which
means that it is flowing in the opposite direction! The integral of the
current density, integrated over the entire cross-sectional area of the
conductor, will of course be equal to the current in the conductor as
would be read by an ammeter.

Not all conductors are solid copper or aluminum. Seawater has been
thoroughly inveatigated in regard to communication with submarines.
Actual RF currents at all depths have been calculated and measured.

Best regards, Richard Harrison, KB5WZI