Re: Heaviside EM Vo 3 info?

On 27 Aug, 05:24, Benj <bjac...@xxxxxxxxxxx> wrote:
On Aug 26, 2:21 pm, blackhead <larryhar...@xxxxxxxxxxxx> wrote:

Well, I can see the above is tongue in cheek, but in all seriousness,
people waste their time on old science  and unknowingly create wrong
theories. I tried to do the same thing with magnetism, viewing it as
retardation effects of the electric field, which is partly true, only
to discover that Einstein 100 years previously had shown that electric
and magnetic forces do not exist independently of the state of the
motion of the system of coordinates, with Minkowski showing 2 years
later that the electric and magnetic parts of the electromagnetic
field depend upon a particular coordinate frame.

Yes, the above was tongue in cheek, but you do realize that you are
essentially saying that a painter can learn nothing at all by studying
the old masters, so it's a waste of time.

I didn't say that at all. I was saying that people try to create new
theories based upon the past and ignorant of what's current. Take a
look at all these new crackpot theories and you'll find the authors
are in the main, educated at a basic level but not upto date. You can
learn from the past, which is far better than doing everything from
scratch, just means it's virtually impossible to do cutting edge
creative stuff.

Such a view is obvious
nonsense. The value of studying old masters is that 1. They possessed
amazing insight and intuition that can stand the test of time. 2.
Their thinking was not inhibited by today's dogma taken for gospel.

Their time created their masters, hampered by convention and dogma
just as ours are today.

The obvious disadvantage of such study is that the old masters did not
have knowledge of modern experimental results that disproved some of
the popular theories of their day. And your mistake is to fall for the
"latest version" scam. This idea, common with software, is that
somehow the "latest version" is absolutely true while all previous
versions are supposedly defective in some manner. A little experience
in life can show that while it is possible for that premise to be
true, it is not always true.  So lets examine Einstein and Minkowski
and what do we find? Well, first you'd better state it correctly to
begin with: The VALUES we MEASURE for electric and magnetic fields
depend upon the particular coordinate frame. The is NO evidence that
electric and magnetic forces actually exchange with each other or the
idea popular today that somehow there are no longer separate electric
and magnetic forces, but instead there is only some "electromagnetic"
force that somehow subdivides according to the frame. Basically the
models for the underlying mechanisms that create electric and magnetic
forces are still unknown after all these centuries!

So? Science progresses, and that's my point. Scientists don't have a
perfect understanding of what E and B are, but the progress since the
time before Faraday when the electric and magnetic phenomena were
considered separate from one another has been incredible.

So I'd say you are correct that using Heaviside as a freshman text is
not a particularly good plan (unless it's a history of
electromagnetics class), but to imply that a re-examination of the
early masters is somehow a waste of time makes no sense. An
examination of history gives one perspective and perspective will tend
to keep the arrogance in check that thinks that the "latest" theories
are all absolutely correct.

Horses for courses. A freshman certainly shouldn't even be looking at
Heaviside and certainly not Maxwell if they want to learn about EM
theory. But as I made clear in my original post, it's when old texts
are being used to create new theories, without looking at what's
current, which is just hopeless.

It's disturbing that so many electrical engineers are completely
unaware of how electromagnetism was revolutionised by Special
Relativity. It's worse than many still thinking there is a causal
relationship between E and B.

I would disagree that EM has been revolutionized by SR. I would argue
that if there is any revolution is would be due to QED. That simply
threw all of Maxwell and EM in the trash can. It's just too bad it's
not particularly useful for making practical calculations.

It's 1 in a series of revolutions in EM:

1. E and B phenomena are discovered by the ancients

2. Faraday shows they are affected by one another

3. Maxwell writes down his equations and shows that light is an EM
phenomenon.

4. Einstein and Minkowski unify E and B by showng they are parts of
the EM field that transform in a way dependent upon the velocity of an
inertial frame.

5. Dirac quantises the EM field, creating QED.

6. Electroweak interaction unifies electromagnetism and the weak force

7 and so on

.As for
relativity, it is possible to show that relativistic electromagnetism
(and thence relativistic mechanics) can be developed solely on the
basis of the principle of relativity plus retardation without any
additional postulated, hypotheses, or conjectures. It seems to me you
gave up on your theory too soon! :)

My naive theory didn't take into account time dilation or the Lorentz
contraction of distance. It was a hopeless muddle, looking back :)
.

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