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Re: Unsolved Questions in Physics

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"Timo Nieminen" <timo@physics.uq.edu.au> wrote in message 
news:0c1c7293-62ec-4b62-bac6-5f0bcc189c9f@googlegroups.com...
On Saturday, August 8, 2015 at 8:02:21 AM UTC+10, Bill Miller wrote:
> On 8/6/2015 7:30 PM, Timo Nieminen wrote:
>
> > What's so say, if he insists that his fig 3.3 field for the pancake is 
> > right, despite simple numerical calculation showing that it's wrong?
>
>   If he doesn't accept the stuff in widely-used EM textbooks (e.g.,
> Jackson) as correct, but insists that he is right and they are wrong,
> what is the point?
> >
> > To have no field along the plane of the pancake requires the pancake to 
> > be an equipotential (along the plane of the pancake).
>
> This, I believe, is where the issue concentrates:
>
>   We know the pancake shaped charge distribution that give an
> equipotential in that plane -
>
> The pancake is *not* equipotential. This was covered in Chapter 1 that
> you do not seem to have read (or grasped) yet.

The footnote on pg 176 explicitly says that it is equipotential.

If the pancake isn't equipotential, there will be in-plane forces acting on 
the charge making up the pancake, and if that moves in the direction of 
those forces, work will be done on it. What Mills writes in that footnote 
about the importance of it being equipotential is quite reasonable.

The field that Mills shows in fig 3.3 would be correct if the pancake was 
actually equipotential.

The error is simply that the charge distribution (3.8) isn't the (known) 
charge distribution for an equipotential pancake.

Mills substitutes (3.8) into (3.9) (which is essentially Jackson (1.5)) to 
obtain his expression for the potential. The integral over z' is easy. Take 
two points in the place of the pancake (say, (x,y,z)=(0,0,0), for which 
Mills gives the result in (3.11), and (x,y,z)=(rho_0/2,0,0)) and compare the 
potentials. Are they the same?

Simple way to calculate Phi(x,0,0) using (3.10) is numerically. Some 
Octave/Matlab code at end of post.

To better than 1%:
Phi(0,0,0) = 4.932
Phi(0.5,0,0) = 4.316

Different. Therefore not equipotential. Therefore, by Mills (3.13), the 
in-plane electric field is not zero, which contradicts fig 3.3 and the 
footnote on pg 176.

> Mills' contribution was the insight that if the charge was not
> equipotential  ie flowing,

In the absence of resistance (i.e., dissipative losses), no problem to have 
charge moving in an equipotential region. Simplest classical example: 
electron moving at constant v in free space.

> and flowing in a certain pattern, then it
> *might* be possible to "build" a physical model that was nonradiative.

Trivial. Just have p(r) and J(r) time-independent in the rest frame of the 
electron. Pretty much every classical model of the free electron achieves 
this. For bound electrons, any model that smears the electron over an 
orbital/shell/ring achieves this.

> I know, Timo, that it is frustrating because you clearly think you are
> talking past me. But you have not yet grasped the concepts outlined
> above. As a result, you are assigning interpretations to Mills' model
> that are different from those that he has assigned.

Even if all of chapter 1 is 100% correct, (3.8) and (3.10) disagree with fig 
3.3 and the pg 176 footnote. That's an error.

> With *any* theory, the same thing can happen if the basic theory is not
> clearly understood.

Doesn't matter what's in the basic theory. If Mills wrote in chapter 3 that 
1+1=17, he'd be wrong. Mills' error with (3.10) is no different: it's a 
simple mathematical error. The correctness or otherwise of his basic theory 
is irrelevant to it.

Since the footnote on pg 176 makes a big deal of the importance of the 
pancake being equipotential, the error appears to be important for his free 
electron model.

Octave (or Matlab) code to calculate (3.10) numerically. Check the 
equipotentialness of the pancake for yourself.

% Numerical calculation of Mills (3.10)

% For convenience, choose units so that rho_0=1,
% and the constants outside the integral = 1.

% Make a simple regular Cartesian grid
points_diam = 1000;
x = linspace(-1,1,points_diam);
y = linspace(-1,1,points_diam);
dxdy = (x(2)-x(1))*(y(2)-y(1));
[xx,yy] = meshgrid(x,y);
xx = xx(:);
yy = yy(:);
rr = sqrt( xx.^2 + yy.^2 );
inside_points = find(rr<=1);
xx = xx(inside_points);
yy = yy(inside_points);

% Let's compare potentials at (0,0,0) and (0.5,0,0)
x1 = 0;
x2 = 0.5;

dnum = sqrt(1-xx.^2-yy.^2);
ddenom1 = sqrt((x1-xx).^2 + yy.^2);
ddenom2 = sqrt((x2-xx).^2 + yy.^2);

Phi1 = sum( dxdy * dnum./ddenom1 )
Phi2 = sum( dxdy * dnum./ddenom2 )

Hi Timo...

First pass... you made excellent points and I apologize for my equating 
equipotential with static.

The charge in Mills' model is in motion in order to achieve nonradiation and 
replicate spin. I put keyboard in motion before thinking about terms.

Let me ponder (& share) your analysis. Will reply as soon as I can -- no 
trout in my immediate future.

Bill 

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Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-07-23 19:21 -0700
  Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-07-25 11:31 -0400
    Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-07-25 19:30 -0700
  Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-07-25 11:50 -0400
  Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-07-25 12:12 -0400
    Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-07-25 21:02 +0200
  Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-07-25 12:26 -0400
    Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-07-25 19:25 -0700
  Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-07-25 20:58 +0200
  Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-07-27 17:52 -0700
    Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-07-29 16:59 -0400
      Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-07-30 13:08 +0200
    Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-07-30 13:15 +0200
    Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-07-30 15:37 -0400
    Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-02 01:53 -0400
      Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-02 11:38 +0200
        Re: Unsolved Questions in Physics benj <none@gmail.com> - 2015-08-02 13:26 -0400
          Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-08-06 12:14 -0400
      Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-02 13:39 +0200
        Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-08-02 18:23 -0700
          Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-03 02:33 -0400
          Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-03 09:04 +0200
            Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-03 14:02 -0400
              Re: Unsolved Questions in Physics Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-03 20:39 +0200
              Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-05 08:40 +0200
                Re: Unsolved Questions in Physics Poutnik <poutnik4nntp@gmail.com> - 2015-08-05 08:59 +0200
          Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-04 08:55 +0200
      Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-08-01 23:27 -0700
      Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-08-02 18:20 -0700
        Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-08-06 12:39 -0400
          Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-08-06 16:30 -0700
            Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-08-07 18:02 -0400
              Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-08-07 18:50 -0700
                Re: Unsolved Questions in Physics "Bill Miller" <kt4ye@yahoo.com> - 2015-08-09 15:55 -0400
                Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-08-11 12:11 -0400
                Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-11 21:22 +0200
                Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-08-11 15:02 -0700
                Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-08-12 11:29 -0400
                Re: Unsolved Questions in Physics shelfstackerextraordinaire@gmail.com - 2015-08-12 16:20 -0700
                Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-08-13 10:09 -0400
                Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-14 19:06 +0200
                Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-15 03:29 -0400
                Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-15 10:48 +0200
                Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-17 04:12 -0400
                Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-17 19:49 +0200
                Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-18 02:01 -0400
                Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-19 19:33 +0200
                Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-20 02:02 -0400
                Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-22 09:41 +0200
                Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-22 15:17 -0400
                Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-08-24 10:51 -0400
                Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-24 15:12 -0400
                Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-08-24 16:35 -0400
                Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-08-24 14:16 -0700
                Re: Unsolved Questions in Physics "Bill Miller" <kt4ye@yahoo.com> - 2015-08-24 21:16 -0400
                Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-25 08:15 +0200
                Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-08-15 10:47 -0400
                Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-15 19:52 +0200
                Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-17 03:51 -0400
                Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-08-17 11:10 -0400
                Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-18 02:31 -0400
                Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-08-17 15:49 -0700
                Re: Unsolved Questions in Physics "Bill Miller" <kt4ye@yahoo.com> - 2015-08-17 20:24 -0400
                Re: Unsolved Questions in Physics Poutnik <poutnik4nntp@gmail.com> - 2015-08-18 07:30 +0200
                Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-18 02:13 -0400
                Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-08-17 23:27 -0700
                Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-18 02:43 -0400
                Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-08-18 10:20 -0400
                Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-19 19:18 +0200
                Re: Unsolved Questions in Physics benj <nobody@gmail.com> - 2015-08-20 01:46 -0400
                Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-14 19:06 +0200
          Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-08-06 16:31 -0700
            Re: Unsolved Questions in Physics Bill Miller <KT4YE@YAHOO.COM> - 2015-08-07 18:05 -0400
          Re: Unsolved Questions in Physics Jos Bergervoet <jos.bergervoet@xs4all.nl> - 2015-08-08 13:21 +0200
    Re: Unsolved Questions in Physics Timo Nieminen <timo@physics.uq.edu.au> - 2015-08-01 16:08 -0700

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