"John C. Polasek" <jpolasek@[EMAIL PROTECTED]
> wrote in message
news:olsi64dpq3djae7k2p3qk1nb92ja7da625@[EMAIL PROTECTED]
> On Fri, 27 Jun 2008 17:23:50 GMT, "Bill Miller"
> <billmillerkt4ye@[EMAIL PROTECTED]
> wrote:
>
>>
>>"Timo A. Nieminen" <timo@[EMAIL PROTECTED]
> wrote in message
>>news:Pine.WNT.4.64.0806260615270.660@[EMAIL PROTECTED]
>>> On Wed, 25 Jun 2008, Bill Miller wrote:
>>>
>>>>
>>>> "Timo A. Nieminen" <timo@[EMAIL PROTECTED]
> wrote in message
>>>> news:Pine.WNT.4.64.0806240535450.1160@[EMAIL PROTECTED]
>>>>> On Mon, 23 Jun 2008, Bill Miller wrote:
>>>>>
>>>>>>
>>>>>> "Timo A. Nieminen" <timo@[EMAIL PROTECTED]
> wrote in message
>>>>>> news:Pine.WNT.4.64.0806221102300.656@[EMAIL PROTECTED]
>>>>>>> On Sat, 21 Jun 2008, Bill Miller wrote:
>>>>
>>>> <snip>
>>>>
>>>
>>>
>>>> Recognition of this simple concept would, as one example, have
stopped
>>>> generations of instructors from teaching their students that E causes
H
>>>> and
>>>> H causes E. It would have also stopped generations of mathematical
>>>> physicists from publi****ng articles in peer-reviewed publications
that
>>>> "proved" that E causes H or vice versa. And it would have stopped
>>>> generations of experimental physicists from spending countless hours
>>>> and
>>>> dollars in building apparatus to measure the non-existent H between
the
>>>> plates of capacitors
>>
>>>
>
>>
>>Herein is the proble: Students are not "pickibg up" misconceptions. They
>>are
>>being TAUGHT them.
>>
>>The participants on this lis are not dumb. But look at some of the
replies
>>in this thread. More than a few folks still harbor the misconception
that
>>H
>>causes E and vice versa.
>>
> snip
>>Strong agreement here!
>>
>>>> Is there a single UG EM textbook that correctly categorizes the
>>>> relation****p
>>>> between E and H? Even ONE?
>>>
>>> Probably. Very likely. But specialised EM texts are the stuff of
>>> advanced
>>> (or at least intermediate) undergrad courses. Those who do just 1 or 2
>>> physics courses ay uni, or only do high school physics never get to
see
>>> them. There might well even be generic introductory textbooks that
don't
>>> get it wrong, by not mentioning it at all. If I have time in the near
>>> future, I will look.
>>
>>Even in introductory texts, it wouldn't be terribly difficult to say
>>something like, "Maxwell's equations demonstrate a clear relation****p
>>between Electric(E) and Magnetic (H) fields. This is sometimes
erroneously
>>interpreted as meaning that E causes H and H causes E. However, a
careful
>>analysis shows that E fields and H fields are sololy caused by charges
and
>>the movement of charges.""
>>
>>Not too hard.
> You are full of beans.
Yep... Had some last night.
As soon as the currents pulse up and down in
> the antenna, a good ****tion of the energy exits as EM waves that take
> off across the country. They're on their own and don't need overt
> charges or currents. E, D, B and H are taken care of by polarization
> of eps0 and mu0, properties of the vacuum. They exchange energies as
> they go along.
Your case would be stronger if E and H (in an EM wave) were out of phase.
Then we would have a situation analagous to -- say -- a spring or water
waves, wherein kinetic energy gets swapped for potential energy, etc.
BUT E and H are in phase! How in the world can anyone imagine that two in
phase and contiguaous signals are *swapping* energy? If you can do so, I
believe we would all love to hear how it works.
THEN stand by your phone for the Stockholm call!
> Your assumption of currents and charges being present and essential is
> just as valid as the teams now looking for Wimps and Machos to explain
> the dark matter problem.
Currents and charges are essential to LAUNCH the wave(s). Afterwards, the
separate E and H signals are in lock step and isolated.
> By the way which do you prefer:
> D = E and B = H
> or D = eps0E and B = mu0H ?
I pick....
Let's see...
Door number... Ummm...Well...
Oh gosh, I just can't decide!
Bill
>>>>>> The rate of Change Of E field in order to deal with magnetic fields
>>>>>> in
>>>>>> a
>>>>>> time-dependent environment.
>
> Whoever wrote the above is unaware that it should be Change of D field
> to affect magnetic fields. Unless D = E.
>
>>>>> I think it is different conceptually. One is a conservation law, and
>>>>> the
>>>>> other describes a limited set of experimental observations.
>>>>
> snip
>>
>> >There was a nice paper by Robert Forward in Proc. IEEE
>>> (or Proc. IRE, if before the name change of the journal) in the 1960s
>>
>>Is this the one in his "Guidelines to Antigravity"?
>>
>>Bill
>>
>>> about the weak-field limit of GR.
>>>
>>
>>> Timo Nieminen - Home page:
http://www.physics.uq.edu.au/people/nieminen/
>>> E-prints: http://eprint.uq.edu.au/view/person/Nieminen,_Timo_A..html
>>> Shrine to Spirits:
>>> http://www.users.bigpond.com/timo_nieminen/spirits.html
>>>
>>
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