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Tony,

It is absolutely crucial that you keep the canary singing. I will not advise you. You have to be on your own.

Ivor   11.8.2020

https://en.wikipedia.org/wiki/Archibald_Howie

 

 

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Re: Charging and Discharging of a Capacitor

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Prof. A Howie

12:17 (2 hours ago)

to Anthony, me, Malcolm, Brian, Forrest, Anthony, Alex, Steve

Dear Tony Wakefield,

Thank you for your message with the further information about your
interesting experiments and the background to them.

The need to pay some attention to the way that the energy stored in a
charged capacitor is actually conveyed across the plates to whatever
connects it to the resistor through which it discharges was I guess a
new idea at the time of your experiments. At least they were described
in Wireless World but did not receive the wider academic attention that
they probably deserved.  Whether this was due to some unreasonable bias
in the academic world of electrical engineering is not clear to me.  I
can certainly see that the campaign to link your experiments to radical
claims that much of the basis of Maxwell's equations is false has not
made it any easier to get more recent academic attention. Nevertheless
(separated from such extravagant claims) they would seem to make a good
project in the training of undergraduates in electrical engineering.

I do not have any personal technical experience in the field of coaxial
cables or transmission lines transmission but have gone to some trouble
to get a grip of the theory of their operation to try to respond to some
of the points that Ivor and his colleagues have been making.  It have
begun to realise that this is a field where assumptions can usefully be
made in practice but which would not generally be valid in
electrodynamics.  The main one is to ignore the frequency dependence of
the behaviour of the wire and sheath which is encapsulated in the ratio
sigma/omega where sigma is the electrical conductivity and omega/2Pi is
the frequency.  This ratio is infinite if we make the most drastic
assumption that the conductors are perfect (sigma = infinity). For high
conductivity metals the assumption is still pretty good even at the
frequencies in the gigahertz range needed to describe suitable pulses. 
This usually means that you can model the progression of such pulses
without having to bring in Fourier analysis.

Perhaps the most obvious inconsistency in the perfect conductor model is
that ohmic dissipation actually occurs and results in some (usually
small) attenuation of the signals.  A full theory taking account of
these effects does not seem to have been developed but approximate
corrections to the simple theory are described e.g in Jackson's book. 
These indicate that in the full theory the waves in the coaxial cable
would have to have a small longitudinal electric field component along
the cable.

Another possibly questionable assumption that I have not had the energy
to look into is the use of simple impedance matching expressions to
describe the wave reflections at whatever terminates the cable. These
expressions are derived for EM waves incident on an infinitely extended
planar boundary and I suspect that they may need to be modified when the
waves are confined within a cable.  I would therefore be interested to
know how accurately the amplitudes of the pulses actually reflected from
the open end of a coaxial cable match with this simple theory.

At least from your response it seems that you reassuringly believe in
electrical current and ohmic dissipation!

In a simple capacitor with circular plates, I have looked briefly at the
problem of conveying the stored energy to connections at the centre. 
This can be done with cylindrical step function waves propagating in and
out along in the radial direction. Starting with the perfect conductor
model, one difference is that the amplitudes of transverse E and B
fields each have to vary like 1/SQRT(rho) where rho is the radial
distance.  This is necessary to keep the constant the energy being
carried across a step fron t of area proportional to rho.  After each
passage of the step the voltage difference between the plates has then
been reduced but NOT equally at all radii.  Some charge redistribution
by normal conduction is then needed.  Secondly the pulse approaching the
origin gets reflected before it reaches the origin and so some
additional ohmic conduction is needed to complete the energy transfer in
this region.

I am increasingly coming to believe that these simple but workable
assumptions made in coaxial cable use are very useful but certainly not
generally applicable across the whole of electrodynamics. Even in the
coaxial cable world the connection with normal current-carrying
processes sometimes has to be made. Similarly in the different field of
house wiring and conventional circuit engineering, the fiction that the
energy is conveyed by the current in the wires may not usually have
serious practical design consequences but it would be interesting to
know of exceptions to this.

Best wishes,

Archie Howie.

f        On 2020-08-11 03:56, Anthony Wakefield wrote:
> Dear Prof Howie,
>
> If you look at the circuit’s for Wakefield 1-4 you will see that
> until the switch is closed the battery is supplying energy to the
> circuit via the 2 x 1 megohm resistors.
>
> Any losses due to the dielectric, moisture, scope probe load and
> resistive is compensated for  until the switch closes.
>
> Now for Wakefield 1-3 these resistors continue to supply energy but a
> very small amount  to the ratio of load applied by the switch.
>
> However with Wakefield 4 the switch is a short (few micro ohms). The
> loses mention account for the decay of amplitude with Wakefield 4.
>
> If we could produce a perfect circuit with zero losses and have text
> equipment that did not extract energy from the circuit then I would
> expect to see Wakefield 4 continue to provide an output of +8 -8
> square waves.
>
> The experiments are very easy to do and I did put out a challenge for
> Academia to maybe do these experiments in a more controlled
> environment. Apart for someone in CERN doing the same Wakefield 1
> experiment in a slightly different way after Wakefield 1 was published
> in ‘Electronics World’,  I do not know of anyone else taking up
> the challenge.
>
> I have attached a PDF copy of my challenge dated 16/12/2018 which Ivor
> has placed on his website somewhere.
>
> I first met Ivor way back around 1968 when I was a hardware designer
> for a new British Computer company. One of the projects was for the UK
> Science Research Council. This was  to capture and process the outputs
> of many instruments at Manchester University. I designed the Analogue
> to Digital and Digital to Analogue interfaces. I use to chat with Ivor
> on many ideas.
>
> I lost contact with Ivor over the next 40+ years but always remembered
> him. Thanks to Google I was able to make contact again around 2011.
> When he told me about his failure to be able to do these experiments
> due to his Test Equipment failure. I looked at the design and came up
> with using a reed switch and a magnet to replace what the very
> expensive equipment did.
>
> I am now 74, have been evolved in  using technology from age of 8 and
> have worked in a number of countries ending up in Australia. Like most
> I did not see the Capacitor as having width that when energy entered a
> plate it had to flow from the connection out to the edge at the speed
> of light in a dielectric.
>
> Regards and thank you for your input
>
> Tony Wakefield.
>
> From: Ivor Catt [mailto:ivorcatt@gmail.com]
> Sent: Tuesday, 11 August 2020 7:34 AM
> To: Prof. A Howie
> Cc: Malcolm Davidson; Brian Josephson; Forrest Bishop; Anthony Davies;
> Alex Yakovlev; Steve Crothers; Anthony Wakefield
> Subject: Re: Charging and Discharging of a Capacitor
>
> Tony Wakefield,
>
> We should have received this many years ago.
>
> Howie is obviously wrong about "ohmic losses". However, we can forgive
> him for that.
>
> The introduction of photons is interesting;
>
> "If you check the discharging description of the coaxial capacitor as
>
> reported by Dr Yakovlev, you will find that the EM wave sprang into
> action at full velocity c immediately when the electrical connection
> to
> the resistor was established.  This is possible because photons have
> zero rest mass" - Howie
>
> So the photons were loafing around, and when the switch closed, they
> all sprang into life. Half of those nearest to the switch hurried out.
> However, the last to come out waited until twice the delay from end to
> end down the coax. Where were the other half of the ones nearest to
> the switch? Where did they wait for double the transit time from end
> to end of the capacitor?
>
> Anyway, when you connected a 20 resistor to the end of a 75ohm
> capacitor, the capacitor went negative and then returned to positive.
> Did some negative photons suddenly appear? Again, plain and simple
> with the Yakovlev explanation that there is no such a thing as a
> static electric field in a capacitor.
>
> What about the case of Wakefield 4, when a capacitor charged to 8v was
> shorted at both ends. The centre of the capacitor alternated between
> +8v, -8v, +8v. -8v. Easy to explain if all the time, even before the
> capacitor ends were shorted, energy was reciprocating from end to end.
>
> " the EM wave sprang into action at full velocity c immediately when
> the electrical connection to the resistor was established." - Howie
>
> Which photons "sprang into action?" Which direction did they travel
> in? How did all photons find out immediately that the switch had
> closed? Was it like "entanglement"?
https://en.wikipedia.org/wiki/Quantum_entanglement
>
> Is Occam's razor not allowed when the canon is threatened?
>
>  [1]
>
> Virus-free. www.avast.com [1]
>
> On Mon, 10 Aug 2020 at 15:21, Prof. A Howie <ah30@cam.ac.uk> wrote:
>
>> Dear Malcolm Davidson,
>>
>> If you check the discharging description of the coaxial capacitor as
>>
>> reported by Dr Yakovlev, you will find that the EM wave sprang into
>> action at full velocity c immediately when the electrical connection
>> to
>> the resistor was established.  This is possible because photons have
>>
>> zero rest mass. Up till that switch on point the field in the
>> capacitor
>> was static i.e. not moving and could have been in that state for an
>> arbitrarily long time. For EM waves to keep running during that
>> possibly
>> long pre-switch on discharge period all the stored energy would have
>>
>> been dissipated by ohmic losses in the coaxial metal components as I
>>
>> said before. I suspect that a more accurate treatment of the coaxial
>>
>> cable discharge taking account of these losses would show that the
>> time
>> constant for the discharge is not just RC but (R+r)C where r is some
>>
>> fraction of the resistance of wire and sheath.
>>
>> Archie Howie.
>>
>> n 2020-08-10 14:35, Malcolm Davidson wrote:
>>> Brian,
>>>
>>> in what way am I abusing the word "static". Here are two
>> definitions
>>> of the word from reputable dictionaries.
>>>
>>> 'staying [1] in one place [2] without moving [3], or not changing
>> [4]
>>> for a long [5] time [6]:'
>>>
>>> 'lacking in movement, action, or change,'
>>>
>>> I ask a reasonable question, but you refuse to answer. As I
>> suggested
>>> to Professor Howie, it's not for scientific reasons, but
>>> psychological, egotistical ones. I will ask the question again;
>>>
>>> How can the stored energy in a charged Capacitor go from 0 m/s to
>> the
>>> speed of light in 0 time? As an adjunct to that question define
>> for me
>>> a region of space where c = 0 m's knowing that all regions of
>> space
>>> are defined by Mu and Epsilon?
>>>
>>> By the way accusatory statements about games etc. show that you
>> are
>>> fearful.
>>>
>>> thanks,
>>>
>>> Malcolm
>>>
>>> -------------------------
>>>
>>> From: Brian Josephson <bdj10@cam.ac.uk>
>>> Sent: Sunday, August 9, 2020 5:00 PM
>>> To: Malcolm Davidson <malcolmd3111@hotmail.com>
>>> Cc: Ivor Catt <ivorcatt@gmail.com>; tonydavies@ieee.org
>>> <tonydavies@ieee.org>; Alex Yakovlev
>> <alex.yakovlev@newcastle.ac.uk>;
>>> Archie Howie <ah30@cam.ac.uk>
>>> Subject: Re: Charging and Discharging of a Capacitor
>>>
>>> This is just more of your word-games and I’m afraid I have no
>> desire
>>> to participate in them.  You are abusing the word static.
>>>
>>> B,
>>>
>>>> On 9 Aug 2020, at 21:54, Malcolm Davidson
>> <malcolmd3111@hotmail.com>
>>> wrote:
>>>>
>>>> if there is a static field as you suggest prior to discharging,
>> how
>>> does the stored energy go from 0 m/s to speed c in zero seconds?
>>>
>>> ------
>>> Brian D. Josephson
>>> Emeritus Professor of Physics, University of Cambridge
>>> Director, Mind–Matter Unification Project
>>> Cavendish Laboratory, JJ Thomson Ave, Cambridge CB3 0HE, UK
>>> WWW: http://www.tcm.phy.cam.ac.uk/~bdj10
>>> Tel. +44(0)1223 337260
>>>
>>>
>>>
>>> Links:
>>> ------
>>> [1] https://dictionary.cambridge.org/us/dictionary/english/stay
>>> [2] https://dictionary.cambridge.org/us/dictionary/english/place
>>> [3] https://dictionary.cambridge.org/us/dictionary/english/moving
>>> [4]
>> https://dictionary.cambridge.org/us/dictionary/english/changing
>>> [5] https://dictionary.cambridge.org/us/dictionary/english/long
>>> [6] https://dictionary.cambridge.org/us/dictionary/english/time
>
>  [1]
>
> Virus-free. www.avast.com [1]
>
>
>
> Links:
> ------
> [1]
https://www.avast.com/sig-email?utm_medium=email&amp;utm_source=link&amp;utm_campaign=sig-email&amp;utm_content=webmail