Dr. George J. Marklin

FEYNMAN VS. EINSTEIN?

There is an interesting remark in "The Feynman Lectures on Physics"
concerning Faraday's law of induction.  Feynman seems to be saying
that Einstein's theory does not actually explain the relativity of
this phenomenon.  Consider the evidence:

Einstein raises the issue in the first paragraph of his paper "On the
Electrodynamics of Moving Bodies":

  "It is known that Maxwell's electrodynamics - as usually understood
  at the present time - when applied to moving bodies, leads to
  asymmetries which do not appear to be inherent in the phenomena.
  Take, for example, the reciprocal electrodynamic action of a magnet
  and a conductor.  The observable phenomenon here depends only on the
  relative motion of the conductor and the magnet, whereas the customary
  view draws a sharp distinction between the two cases in which eigther
  the one or the other of these bodies is in motion.  For if the magnet
  is in motion and the conductor at rest, there arises in the neighbor-
  hood of the magnet an electric field with a certain definite energy,
  producing a current at the places where parts of the conductor are
  situated.  But if the magnet is stationary and the conductor in motion,
  no electric field arises in the neighborhood of the magnet.  In the
  conductor, however, we find an electromotive force, to which in itself
  there is no corresponding energy, but which gives rise - assuming
  equality of relative motion in the two cases discussed - to electric
  currents of the same path and intensity as those produced by the
  electric forces in the former case."

Then at the end of section 6 in the same paper, after deriving the
transformation equations for the electric and magnetic fields, Einstein
concludes:

  "Furthermore it is clear that the asymmetry mentioned in the intro-
  duction as arising when we consider the currents produced by the
  relative motion of a magnet and a conductor, now disappears."

Clearly Einstein is claiming to have solved the problem - to have
provided a unified explanation of the two different phenomena.

But then consider the following statement by Feynman at the end of
section 17-1 in volume II of the Feynman Lectures on Physics, right
after he explains the flux rule relating the e.m.f. in a conductor to
the changing flux from a magnet in relative motion:

  "We know of no other place in physics where such a simple and accurate
  general principle requires for its real understanding an analysis in
  terms of two different phenomena.  Usually such a beautiful generali-
  zation is found to stem from a single deep underlying principle.
  Nevertheless, in this case there does not appear to be any such
  profound implication.  We have to understand the 'rule' as the combined
  effects of two quite separate phenomena."

Feynman was an expert on relativity and he would certainly have been
familiar with the above remarks from Einstein's paper.  So when he
says that "there does not appear to be" any "single deep underlying
principle" this can only be interpreted to mean that he doesn't believe
that the theory of relativity actually provides a unified explanation as
Einstein claimed.

Could he perhaps have meant that Einstein only provided a unified
description of the different phenomena but not a unified explanation?

Dissidents like myself are routinely criticized for daring to suggest
that the theory of relativity only provides a correct description of
nature, but not a correct explanation.  It would be good to know that
Feynman was on our side, if he actually was.

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