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Re: Poynting Vector Vortex Experiment



Original poster: "Paul Nicholson by way of Terry Fritz <twftesla-at-qwest-dot-net>" <paul-at-abelian.demon.co.uk>

Hi All,

Richard Wayne wrote:
> ...challenges and completely destroys their long cherished belief
> system.

What belief system would that be?  We use EM because it works. 
Frankly, many a time I would welcome a simpler set :).  I for one
am a hard nosed sod and don't believe anything at all.  If it makes
sense and works, I use it.

> Usually these folks are quite rigid and inwardly have doubts about

Correction: it is nature that is rigid.  That feature, noticed by
the Greeks, enables a law to be formulated on Monday, and it still
works on Friday.  Nature does things in certain ways, and both we and
scientists have to live with that.  Our beliefs don't count.

> Displacement Current was a fantasy invented by Maxwell to make his
> mathematical equations work correctly.

It was the missing piece of a puzzle, in which Maxwell had before him
all the various known laws: Faradays, Amperes, Coulomb, etc.
They just wouldn't fit together without this piece, and Maxwell was
forced to include it, initially for mathematical reasons.  It rather
made the scientific world sit up,  because here was a completely
unknown phenomena (at the time, radio waves) which was predicted by
what amounted to mathematical necessity.  Before then, scientists
had patiently quantified things and made up laws from the patterns
they saw.  Then suddenly we find this solitary Scottish mathematician
saying that a whole new class of phenomena ought to exist!  It is
truly remarkable that a hitherto unknown phenomena can be predicted
this way, and it was quite a shock to 19th century science.  Nowadays
we are more used to theoretical predictions of entirely new and
unsuspected things, eg time dilation; W and Z particles; 

>  It has never been proven experimentally although its proponents
> swear it exist.

It is not a matter of belief that radio works, you can easily test it.
This feature of Maxwell's equations is tested every time you use a
radio wave.  This has been pointed out several times now.  Here we see
the true believer syndrome.  Richard has failed to explain radio
propagation in the absence of dD/dt coupling to H, instead, he merely
repeats his assertion.

> Proponents always manufacture a reason why it cannot be measured
> in reality or it is explained away with another equation or theory.

The onus is on Richard to explain quantitatively the voltage induced
across the terminals of a distant dipole, without including any term
involving dD/dt.

> I do, however, encourage anyone interested to experiment and
> demonstrate positively to the world that Displacement currents
> really exist.

Continuing the theme of denying the existence of a commonly observed
phenomena.
 
> When someone stakes out a theoretical claim (Maxwell included) the
> experimental burden of proof is on that person to prove it..

Rarely, these days.  It is much better, more efficient, and *safer*
for someone else to do the experiments.  Reasons:
a) It forces the theorist to explain himself properly, sufficiently
well for others to test the ideas.  That strengthens good theories
and quickly disposes of the junk.
b) The technical skills required to do good experimental work are
very different to those needed by a theorist.
c) Perhaps most importantly, it is very risky for the creator of an
idea to try to validate it himself.  The very human tendency to see
what you want to see it shockingly powerful.  The best experimenter
is the one who is rather skeptical of the theorist's claims, and who
sets out to disprove them.  

Lacking (a), we often see crank experimenters carrying out meaningless
experiments on nonsense 'theories', and it is sad to watch.  For
example, if Dave could say exactly what he meant by a longitudinal
wave, it could then either be tested by new experiments, or refuted
immediately by referring to the results of previous experiments or
the laws formed from them.

> Are we trying to dismantle Maxwell's equations and EM theory in
> general?  No.

Correction: Yes, if you wish to remove the term dD/dt, it dismantles
EM and a couple of other non-trivial things too.

> We are merely trying to point out their shortcomings and establish
> the fact that they are but a subclass of a much larger and more
> inclusive electrical theory.

The shortcomings of Maxwell's equations are well known, and there are
a couple of layers of deeper theory which resolve the issues in cases
where quantum effects become noticeable.

> Has anyone tried to apply them to electrostatics?

Maxwell's theory includes the laws of electrostatics.

> They fail miserably.

Correction: they work extremely well.

> But, there is a much more advanced Electrical Theory out there. 
> It does not supplant, but enhances EM theory which is a subclass of
> this greater Electrical Theory.  We did not invent this theory for
> it was devised over a century ago.  It's only being rediscovered. 

Ah, the inevitable intimations of secret knowledge...

> Now even the thought of it is forbidden in Electrical Engineering
> schools.  They will not be able to suppress this knowledge forever.

...and the accusation of conspiracy by the establishment.  Too much
Fox TV.

> What I simply propose is take a look at EM as a three dimensional
> entity rather than in two dimensions. 

Correction:  EM is a 4-D Lorentz-invariant theory.  The math is much
simpler when written down against a 4-D co-ordinate system, you
just end up with a single neat and simple equation that describes
the whole lot.  In 4-D, the separate vectors of E and B are clearly
seen as a single field entity, described by an object called a
'tensor' rather than a 'vector'.  After the initial obstacle of
learning tensor calculus (as if vector calculus wasn't hard enough!)
the payback in terms of greater clarity of the theory is worthwhile.
The relation between E, B, space, time, and the observer of the field
becomes much simpler and clearer. 

> Instead of just E and B there is always an attached S vector. 

The S vector is called the Poynting vector and is *defined* to be
E x H  (to be read as E cross H, where 'cross' is the vector cross
product).  It isn't another component of the field, but relates to
E and H in the same way that length and breadth relate to area, or
that volts and current relate to power.  The S vector points in the
direction of energy flow.  Just like you can have real power and
reactive (or complex) power, you can define a complex S vector, E x H*
where H* is the complex conjugate of H.  Integrate S to obtain the
energy density of the field.

> All three oriented at right angles.  Just like the 3D space we live
> in, they are always inextricably linked

Another misdirection: Richard is trying to make out that S is a third
polarisation vector, on the same footing as E and B, rather than
simply their cross product.  It is like confusing voltage and power.

> This additional coordinate in the system doesn't exclude common EM
> theory, but vastly enhances it.

The Poynting vector, and Poynting's theorem, which describes the law
of energy conservation in an EM field, are well established parts of
EM theory.

> Poynting also worked out the mathematics of an additional vector,
> S, in relation to E and B.  He was ignored and forgotten.

Another misdirection.  Look in any book on EM theory to find a chapter
on the Poytning vector and its applications.  The Poynting vector is
used extensively in things like antenna design.

> The important thing is to realize the relationships of S = B x E are
> universally there all the time.

Correction: S = E x H.   If you use  H x E or B x E, the resulting
vector points the opposite way.  The vector cross product
anti-commutes, ie H x E = -(E x H).  We defined S to be E x H, so
it's there for as long as we want it to be.  We defined it that way
so that it represents the power flow in the field.
--
Paul Nicholson
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