Re: "4/3 Problem" Resolution (fwd), comment on

[Jack Uretsky <jlu@HEP.ANL.GOV>]

Hi all-
        This posting will be my last comment on this thread.
        David presents a classical calculation purporting to show that
the electron mass is purely electromagnetic in origin.  A crucial
element of his calculation is that it violates gauge invariance.
Gauge invariance is a basic principal underlying 50 years of quantum
mechanical calculations as well as classical calculations (such as
EM waves in wave guides).
        David shows us no other desirable consequence of his violation
of gauge invariance than his purported demonstration that the electron
mass is purely electromagnetic in origin AND can be calculated
classically.  He now challenges us to choose between his calculation
and gauge invariance.
        The classical calculations, by the way, as I have pointed out
earlier on a similar thread, disagree totally with the QED calculations.
        Thank you very much, David.
                                        Regards,
                                                Jack




On Wed, 16 May 2001, David Rutherford wrote (in relevant part):

> On Wed, 16 May 2001 11:12:36 -0500, Jack Uretsky <jlu@HEP.ANL.GOV> wrote:
>
> > On Wed, 16 May 2001, David Rutherford wrote (in relevant part):
> >        [Uretsky had written]
> > > >        Specifying curl(A) is not the same as specifying A.  Since the
> > > > curl of a gradient is zero, I can add any gradient to A without changing
> > > > the value of the curl.  But there is an infinity of gradients that will
> > > > change the value of div(A).  That's part of the principal of gauge
> > > > invariance.
> > >
> > > Then it's incumbant on you to find a condition under which the value of
> > > div(A) is not changed or you must dump the concept of gauge invariance,
> > > because div(A) is definitely specified. In this three-dimensional, time
> > > invariant case, gauge invariance is only possible if the condition
> > >
> > > d^2(/\)/dx^2 +  d^2(/\)/dy^2 +  d^2(/\)/dz^2 = 0
> > >
> > > is satisfied. If you don't choose to accept that condition, then you have
> to
> > > abandon the validity of gauge invariance for this case. Periodisimo.
> >
> >        Ahh, there we have it.  David's quarrel is with gauge invariance.
> >        But the principle of gauge invariance derives from the statement
> > that only the fields are physical.  The potentials (A and phi) are not.
>
> Div(A) involves the _derivatives_ of A, not A. The derivatives of A are
> physical, therefore div(A) is physical.
>
> >        Stated otherwise, it is the Maxwell equations, expressed in terms
> > of the E and B fields that completely describe classical electrodynamics.
>
> They don't describe a totally electromagnetic mass.
>
> > David evidently wants to make some condition on div(A) an addition to
> > the Maxwell Equations (that is, a gauge-fixing condition).  Such a
> > condition would have far-reaching consequences,
>
> Now you're catching on.
>
> > because all accepted calculations to date insist on gauge invariance.
>
> Not my fault you guys got it wrong.
>
> > A recent relevant example is the eight order (in charge) calculation of the
> muon g-2 done over the years by Kinoshita and others.
>
> How does that affect what I've said?
>
> Regards,
> Dave

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                     <The 5-MINUTE ILIAD and Other Classics>