Talk:Ivor Catt/Archive 16
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Catts error
I've added responses to Kevin's previous rebuttal above where he makes the errors. The major error of Catt is confusion over charge and electric current. He variously uses and dismisses these concepts. The facts are:
(1) An old style CRT television throws electrons at the screen. You can feel the charge because the hairs on the back of your hand and raised by the electric field. Put a Catt near a television and the fur will stand on end ...
(2) Similarly, all valves (whoops, vacuum tubes for US readers) work by electron flow from hot cathode to anode (electric current goes the other way to electron current due to Franklin's convention).
Where the mainstream is wrong is in not explaining why the current flow occurs. Take the Catt Question diagram. Ignore for the present the ramp part (which I deal with here: http://feynman137.tripod.com/ ).
How does an electron current flow in the flat-topped part (behind the step front or rather ramp) of the logic pulse where the voltage is the same value along the conductors?
Ivor Catt indicates in the middle of his book "Electromagnetism 1" that magnetic field interaction between the two opposite currents in the conductors allow the current.
This seems to be vital: it is not electric field gradient along the conductor which causes the current for situations behind the logic step front, but magnetic field! In a single wire you can't have a steady current flow because the magnetic field (self inductance) is infinite, but for a pair of nearby conductors carrying equal currents in opposite directions,the resultant curls curls of magnetic fields from each conductor at long distances cancel out perfectly so the inductance is then limited, allowing transmission of current.
To summarise: at the rise or ramp of the logic step, electric field (or voltage gradient) along the conductor (from 0 volts to the flat peak of v volts over distance x = ct where t is the rise-time) occurs. This electric field is E = v/x = v/(ct) volts/metre, which induces an electric current by accelerating passive 2s conduction electrons in the conductors to a peak net drift velocity (they are normally whizzing around at random at a speed of c/137). Once the flat v volts is attained, the electric field is no longer able to accelerate electrons to overcome resistance, but the magnetic field from the opposite conductor induces a current flow as per Catt "Electromagnetism 1" 1994. Nigel 172.216.69.195 10:03, 16 May 2006 (UTC)
- Nigel, you condsider Catts diagram as being in the steady state, in which case your objection might have some validity. However, Catts diagram does not show the steady state but is merely a snapshot at an instant in time.
- For a zero risetime of the step, all frequencies would be present from zero to infinity in the wave form. How and where do these frequencies exist if not in the line? You cannot consider the shelf of the travelling wave to have no ac component. If you were to setup a TL pulser, at a rep rate of 100 kHz, say, you would see a 100kHz fundamental with harmonics extending to infinity. Your assumption implies that there would be no fundamental and none of the harmonics apart from the very high ones corresponding in wavelength to the 'ramp' you have shown. Why can you say with such certainty that a single isolated pulse travelling down a line is going to behave differently from a train of similar pulses? And does it make any diff to the analysis. I say it makes no difference.
- So instead of treating the problem as one of a single pulse, what actually happens can be shown by analysis of a TL pulser. In this respect, maybe its misleading to try to analyse a single ideal pulse, as we know that it cannot be realised.
- I dont believe in Disp Current anyway. Nothing physical passes from one wire to the other but the conductors are coupled by the electric and magnetic fields.--Light current 12:53, 16 May 2006 (UTC)
- No I don't. See diagram above. Nigel Cook 82.22.34.205 15:26, 16 May 2006 (UTC)
- Thats your diagram isnt it?--Light current 22:03, 16 May 2006 (UTC)
- That's what I've pointed out. Nigel 82.22.34.205 15:26, 16 May 2006 (UTC)
- Light current, this is exactly the point I've made above: the rise portion is in time and space, and the portion behind the rise is constant in time and space (the energy is flowing but the voltage is not varying in space or time behind the ramp portion at the front or RIGHT HAND SIDE, see the diagram above). The time-variation in the field ramp portion as it overtakes (sweeps past at light speed) very slow slow electrons creates electromagnetic radiation emission. Nigel 82.22.34.205 16:13, 16 May 2006 (UTC)
- What rule allows you to split the rising edge off from the rest of the wave? 8-) --Light current 21:57, 16 May 2006 (UTC)
- No you wouldn't! The frequency is the number of cycles per second. Once the ramp part has passed, the constant voltage portion of the logic step to the left has a frequency of zero Hertz. Nigel 82.22.34.205 16:13, 16 May 2006 (UTC)
- You cant have one without the other!--Light current 21:57, 16 May 2006 (UTC)
- I'm too stupid to grasp what your question is! What "train of similar pulses" do you mean? Morse Code? Theoretical square waves, sine wave AC, what? I'm discussing a battery connected to a transmission line, which is what the discussion is about. Are you discussing the Catt stuff? This is the discussion page for the Catt stuff. Nigel 82.22.34.205 16:13, 16 May 2006 (UTC)
- A train of similar pulses is just that. One positve step followed by a negative step- a pulse waveform as in a TL pulser! (radar modulator)! I know what the page is about. --Light current 21:57, 16 May 2006 (UTC)
- What makes no difference? What are you comparing to the battery connected to a transmission line, Light current? Square waves, sine waves, what? I can't guess what you are comparing to the situation we are discussing. However, if you simply mean that AC is the same as DC then you are totally wrong. AC will propagate in a single wire which acts as an antenna, radiating radio waves with a frequency of 50 Hertz. DC doesn't do that. If you have a pair of conductors as a transmission line fed with AC, each conductor will radiate an inverted wave form radio signal to that radiated from the other one. Hence no radiation can theoretically escape to a distance because the superimposed signals exactly cancel (in practice this often doesn't work perfectly because the wires are not identical transmitters and you get some net radiation). The propagation of an AC energy current by a transmission line is different from a DC current. Nigel 82.22.34.205 16:13, 16 May 2006 (UTC)
- Light current, have you ever connected a pair of wires to a battery so that a steady voltage propagates at light speed down a transmission line? Isn't this the situation that "cannot be realised"? I can't believe how impossible you are being! Nigel 82.22.34.205 16:13, 16 May 2006 (UTC)
- Yes I have. No it isnt. It cant actually be realised because the line voltage would need to be zero for infinite negative time and V volts for infinite positive time. Both are impossible! Why do you say Im being impossible?--Light current 21:05, 16 May 2006 (UTC)
- The electric and magnetic fields deliver energy. Put a magnet above a paper clip, and the paper clip gets the energy to accelerate upwards. The magnetic field is delivering energy through the intervening space. This is why I have labored the point that the Catt situation tells us about the reality of quantum field theory. Nigel 82.22.34.205 16:13, 16 May 2006 (UTC)
- I dont thikn we need QFT to expalin this stuff yet!--Light current 21:57, 16 May 2006 (UTC)
- So, Nigel, you're trying to argue that disp current does occur but only at the leading edge osf the step? Of course your defn of disp current differs from mine. You say it is em radiation. You say radiation passes from one wire to the other in the vicinity of the step but nowhere else? Of course my position is that em energy is present everywhere in the line (even the flat part)and in your diag its travelling to the right. If you attach a resistor to the end of the line you will notice this energy being dissipated. Its travelling at 'c' for the medium into the resistor. So how does the dc at the back of your step get converted into em radiation if it is not already in fact em radiation?? Behind your step, its true that there are no voltage variations, but opposing, progressing mag fields must surround the conductors. The energy in these fields cannot just disappear into thin air (or vacuum) it has to continue flowing. Thats why I say you cant ignore the back of the wave-- energy is travelling in all of the line behind the wavefront toward the load.--Light current 16:06, 16 May 2006 (UTC)
- Science isn't about saying "I don't believe in displacement current", or "I do believe in it". That's religion. I'm sticking to the facts. The electrons cause the pulse propagation according to known facts. This doesn't rule out "displacement current" entirely. Obviously you have to deal with real non-vacuum capacitors that have a different permittivity like plastic, where there may be a contribution from a real displacement current. Also the vacuum contains some virtual charge which gets polarised according to quantum theory. But that will become polarised as a result of the light speed fields, ie as a secondary effect not a primary cause. If it contributes, it is likely to deliver little energy, just as electron drift current delivers insignificant electrical energy compared to the light speed electromagnetic field.
- What you are saying is that the field is moving at light speed, which I agree with 100%: all non-nuclear fields always go at the same speed in a vacuum, light speed. This is the same for magnets and static charges as in a TEM wave with electromagnetic fields propagating. Nigel 82.22.34.205 16:24, 16 May 2006 (UTC)
- Nigel, I see that you're running the "not enough kinetic energy" argument again. It has struck me recently that in all the words we've exchanged on the subject that the point has not been made that in order to accelerate an electron it is necessary not only to supply the energy needed for the kinetic energy of the electron's moving mass, but also to supply the energy needed for the magnetic field that results from the electron's moving charge. -- Kevin Brunt 16:40, 16 May 2006 (UTC)
- Good point Kevin? 8-?--Light current 21:18, 16 May 2006 (UTC)
- As stated, the magnetic field is co-eternal with the electric field. Every electron has a magnetic field (a magnetic dipole moment). Some of the above replies by me have either been changed with Light current's responses or result from the "Somebody has changed the content since your edit" which I got on 16 May. The programming on Wikipedia means that when you type a reply and someone in the meantime makes a quick change to a comma or something and saves it, then Wikipedia won't accept your modification. It reminds me the Catt Anomaly. A load of nonsense. Bests, Nigel 172.202.216.233 13:05, 20 May 2006 (UTC)
- Nigel, restrict your edit a single paragraph, or to a single block of new text. Then if it gets bounced, it's easy to use the "Back" button on your browser to go back to the edit box, select and copy your text, "Back" once more to the "main" page and repaste your text into a new edit. The "conflicting update" is a classic issue with parallel processing. Much of my scepticism over Catt's Kernel Machine lies in the lack of any discussion of the synchronisation issues in his writing. -- Kevin Brunt 18:32, 22 May 2006 (UTC)
All DC is ultimately AC
I do have a very slight (almost imperceptible) feeling that there is some common ground between me and Nigel (and between me and Kevin). However because Nigel and I are talking different languages, a lot gets lost in the translation. I am trying to find the best way of exploring this common ground, but its difficult. Basically, each respondent in this discussion should respond directly to the others points rather than flying off at tangents. This will aid understanding of each others POV. I will say this only once. Listen carefully. All DC is ultimately AC Think about it! 8-)--Light current 21:37, 16 May 2006 (UTC)
- LC, I've no quarrel with your "DC is AC" thought, but it would shed more light on Nigel's diagram to note that both the "step" and "ramp" versions represent a transition between 2 DC situations. Ahead of the "step" no current is flowing; behind it a current of magnitude V/Zο flows. Any length of the line (up to and including the whole of the line) which contains the step has a net imbalance of current; this imbalance is, properly speaking, what "displacement current" is. What Maxwell did was to show the relationship between the accumulating charge and the electric field it causes. Where this really ties back to the original Catt et al article, is that it does not matter whether the charge progresses down the line behind Catt's step, behind Nigel's ramp, or as the extreme case where the ramp extends the whole length of of the line, so that the voltage is the same all the way along; whatever the exact location of charge is, the total change in the field is the same and satifies Maxwell's observation that the displacement current is equal to dQ/dt which is equal in magnitude to dD/dt. The "whole line" extreme is effectively the one that Maxwell used when he originally derived dQ/dt + dD/dt = 0. Catt's real error is that he does not understand that Maxwell chose the "equal voltage" case entirely because it was the simplest one to do the calculations for; it was a purely hypothetical situation, and in no way meant that Maxwell claimed that it would happen in any real situation. -- Kevin Brunt 20:52, 19 May 2006 (UTC)
Wave dismemberment
Why are you trying to dismember the wave? Are you allowed to do that? I dont think you can treat the wave as two separate portions. Also, all the wave on the line is ac. DC does not exist!--Light current 22:40, 19 May 2006 (UTC)
- LC, I can't see any "wave" to dismember! Whichever way the situation is viewed, you end up with two parts. If you start with charge, you end up with voltage (due to location of charge) and current (motion of charge.) If you start with the E×H of Heaviside's energy current you end up needing to explain where charge comes in. Catt started by dealing with the energies stored in the inductance and capacitance separately, and showing that they are necessarily equal. There is some sort of basic "twoness" - two aspects of the same thing. -- Kevin Brunt 00:51, 20 May 2006 (UTC)
Imbalance
What do you mean by a net imbalance of current behind the step? The current flows to the right along the top conductor, and back to the left along the bottom one. This is not an imbalance!8-|--Light current 23:10, 19 May 2006 (UTC)
- LC, No! My point is specifically that there is no net imbalance behind the step, or in front of it for that matter. However, as long a step travelling down a TL does hit an impedance mismatch, the current flowing behind the step is related to the voltage ("height") of the step by the TL's characteristic impedance. The voltage step is also a current step, and for any length of the line that includes the step, the current flows at the two ends will differ. Any length of line which does not include the step will have identical currents at each end. This exposes one of Catt's obfuscations, because a correct analysis of Catt's TL-as-a-capacitor scenario reveals the voltage step always marks the point where the folw of current from the voltage source stops, even when the "reflected" step is travelling backwards to the input end. Thus the displacement current is always happening just at the point where the charge current stops flowing along the wire and needs to "cross over" to the other conductor (very loosely speaking.) -- Kevin Brunt 00:32, 20 May 2006 (UTC)
You seem to be agreeing with Nigel partly about disp current. Youre saying that there is a (displacement) current flowing from one conductor to the other, but only at the leading edge of the step? You say the current at both ends of the line containing the step will differ. Do you mean that beyond the travelling edge there is no current in the conductors? If so I agree- the energy hasnt reached there yet!. This is not a problem and I dont see what you are driving at here.8-? THe 'flow' of current doent stop here - it continues to travel along both conductors! I cant see any obfuscation by Catt regarding the flow of Heaviside energy current.8-? But I agree that his diagram (and Nigels) showing any sort of 'current' or anything physical is WRONG! There is NO cross over of current. That is a fallacy -- there maybe be induction but thats another story!--Light current 10:54, 20 May 2006 (UTC)
- Yes, there is displacement current at the travelling edge, more or less by definition, because voltage is a manifestation of electric field and where the voltage is changing the field is changing, and that is displacement current. Where I differ from Nigel, is that he seems to think a TL has to have parallel conductors. (Let's tie him up in knots by discussing the impedance of free space, where there are no conductors.... :) ) My position is that the electric field surrounds the voltage step in 3 dimensions; the presence of another conductor will affect the shape of the field, but not the essentials. The electric field stores energy, but does not of itself transfer energy elsewhere. However, if the field interacts with another one (such as that of the charge in the other conductor) the interaction will result in creation of a force. If that force causes motion, a transfer of energy will result (as required by basic mechanics...) Catt's obfuscation is his repeated assertion that there is no displacement current, which we are showing to be false by looking carefully at Catt's own example. -- Kevin Brunt 19:49, 20 May 2006 (UTC)
I paraphrase from te archives:
The fundamental questions. Would either (both) of you care to define exactly what you each mean by the term 'displacement current' (in vacuo).
Q1 Is it for instance:
- a) a flow of electric 'displacement' as User:Alfred Centauri would have it?
- b) dD/dt ( which may be the same as above)?
- c) electromagnetic radiation?
- d) nothing at all (ie doesnt exist)?
- e) something else? if so, what?
Q2 In which direction does it flow if it exists?
- a) from one plate of a parallel plate capacitor to the other plate (orthogonal to the plates) via the dielectric( eg air/vacuum)
- b) parallel to and between the plates
- c) in some other direction. If so - what direction?
Kevins position Thus, "displacement current" really means "there is a changing electric field here". I would tend to go with answer b) to Q1 (but wih reservations). Answer a) is probably putting too much "meaning" in. Answer c) has serious problems about the distinction between what displacement is, and what it causes. Answer d) is wrong, because there is a changing magnetic (I meant electric!) field. Answer e) has at least some truth in it. -- Kevin Brunt 15:39, 24 February 2006 (UTC) As for Q2; firstly there is an issue with the "flow" - it assumes that the changing electric field is actually moving something, which moves the debate unnecessarily into the realms of quantum mechanics, etc, etc. For the purpose of understanding electromagnetism, it is only necessary to know that the field "is". As for the direction it acts in - it exists in 3D around the charge, so it operates in all directions. However, it interacts with its environment, so Q2 can really only be answered in the context of a specific situation. -- Kevin Brunt 16:00, 24 February 2006 (UTC)
--Light current 20:21, 20 May 2006 (UTC)
I agree there is a changing electric field at the step. I do not call this displacement current. I dont call it any thing except dD/dt. I indeed at the moment i am considering the case primarily of TEM inside a coaxial cable because we dont have to consider stray fields extending to infinity (ie its the simplest case). Your 3 dimensions can be dealt with inside the coax. I urge you to stick to this example if at all possible in the first instance before going on to // wires and free space propagation. Are these limitations acceptable to you at the moment? Also the flow of current from the voltage source doesnt stop until the line is fully charged (twice the electrical line length). --Light current 20:30, 20 May 2006 (UTC)
Could we all please stop using the term displacement current? The word current means a 'flow' of something. As each of us has his own definition of it, can we please all say exactly what we mean. Ie
- real currernt (ie flow of charge(s))
- em radiation,
- dD/dt,
- magnetic fields
- flow of ghosty-ghoulies etc
Thanks. It'll save a lot of wasted time (Ive got other pages to edit) 8-(--Light current 20:58, 20 May 2006 (UTC)
- Might I suggest that the precise definition of "displacement current" is that it is the label used by physicists to refer to Maxwell's work on the relationship between charge, electric field and magnetic field which completed the four equations describing electromagnetism, now referred to as "Maxwell's Equations". The term "displacement current" is obsolete and somewhat misleading, since it is not a concept of electromagnetism itself, but instead is associated with Maxwell's attempts to explain electromagnetism in terms of an underlying fluid "Aether". The Aether (at least as Maxwell conceived it) was abandoned after Maxwell's death as the accumulating experimental data made it increasingly untenable. -- Kevin Brunt 19:55, 22 May 2006 (UTC)
- NB What I do disagree with is the statement that the flow of current/energy/whatever in a conductor is "TEM", if by "TEM" you mean "transverse electromagnetic" in the same sense that physicists do when refering to "electromagnetic radiation". The latter usage is associated with a family of equations describing the electric and magnetic fields which satisfy the constraints of Maxwell's Equations in the specific case that the J term in the Ampere-Maxwell law is zero. This explicitly excludes the "flow in a conductor" case, because it can be easily shown (by considering the case of a TL properly terminated at each end) that the "plateau" following the initial step of a pulse is identical to the "steady-state" situation predicted by Ohm's Law and Kirchoff's Laws, and there is therefore current flow which is, by definition, a non-zero J value. -- Kevin Brunt 20:16, 22 May 2006 (UTC)
Catt and "The History of Displacement Current
- What I think we need in the main article is a section entitled Catt and "The History of Displacement Current", which discusses the article of that title which was published in Wireless World in March 1979. It would appear to be the article referenced in the December 1978 article which did not get published in Physics Education. Catt complains that the Institute of Physics "broke their contract"; it would be much fairer to say that Catt, Walton and Davidson failed to deliver the article that the IoP expected, and that the article that was delivered was simply not good enough to publish. Catt's annotation at the end of the article is illuminating; he still thought in 2004 that nobody before him had considered that charge does not spread instantaneously across the plate of a capacitor. This is, of course, nonsense; you don't need to look any further than the derivation of the Telegraphers' Equations to find a counter-example. Catt's problem is that the "spread of charge" issue is sufficiently complex and abstruse as to be an "advanced topic"; it needs the deployment of the full mathematical description of a capacitor and that required calculus. The full equation of the charge on a capacitor is not Q=CV; that is merely the result of an integration of a simple case. If you look at Nigel's diagram, you ought to be able to see that it is effectively a graph of V against x at some instant in time. It should be obvious that for any finite x the area under the curve is proportional to the charge on that length of the line, and that in consequence it can be shown that dQ/dx = C dV/dx. A little thought will show that at any point on the line, the graph of voltage against time is the mirror image of Nigel's diagram, with time along the horizontal axis; thus we can say that dQ/dt = C dV/dt. I'm not going to try to put these together, but what we'd get is a partial differential equation relating Q and V, where both are not simple variables, but functions of t and x (and y as well, for the more general case of a surface.) I would say that there is ample evidence that Catt's mathematical competence does not extend to this sort of calculus and that he simply can't follow the textbooks that do deal with arbitrary charge distribution. -- Kevin Brunt 21:41, 19 May 2006 (UTC)
What I think is that that stuff should be put in the Displacement current article.8-|--Light current 22:33, 19 May 2006 (UTC)
- Catt's article (and footnotes) don't have very much to do with displacement current, but a lot to do with Catt's misconceptions. -- Kevin Brunt 01:15, 20 May 2006 (UTC)
I still think it should go in Displacement current. Other editors will tell us if its misplaced there (eventually) 8-|--Light current 22:00, 20 May 2006 (UTC)
- They definitely won't think much of it, because it simply isn't about the history of displacement current. It's really the rest of the Dec 78 Wireless World article. I suspect a parallel between this article and Catt's 1969 article in New Scientist on computer architecture. Somewhere on his web sites he boasts of having deceived the NS editor about the content of the article. This time the IoP editors just said "No". -- Kevin Brunt 23:00, 20 May 2006 (UTC)
Try it and see!--Light current 23:06, 20 May 2006 (UTC) This link at the end of the following points right back to the top of this article -- that doesn't seem correct.
extract from Electromagnetic Theory Volume 2, Ivor Catt, St Albans, 1980, pp. 207-15 - [3]
I put this quotation in, in the first place. The link I placed was [2]. Someone obviously changed the link to the Wikipedia page afterwards (making it a ridiculous self-reference; a bit like writing a book and having all the end notes cite the same book as source!). I think that this illogical link change must have been done by someone with entirely circular reasoning, say a member of the string theory community, or an expert on entangled explanations of the wavefunction collapse. ;) 172.143.55.86 10:12, 24 May 2006 (UTC)
Catt-Lynch sub-theory
LC, Nigel is arguing the the Catt-Lynch sub-theory, which is basically an "argument from incredulity" over the disparity between the electron drift velocity and the velocity of propagation. At the end of the day, the average velocity of the conduction electrons (which is what the electron drift velocity is) will match the strength and direction of the magnetic field. Rather than trying to argue as to whether the movement of charge causes the electric and magnetic fields, or vice versa, is ultimately futile as you just can't have one without the other. (NB I am not arguing against TEM waves in free space; there are important differences, about which Catt has obfuscated this last quarter-century.)
It ought to be obvious that the fields and the charge motion must be considered as a whole, as inductance and capacitance can only be explained understanding the fields, while resistance cannot be explained by any theory that is not intimately tied in with the nature of the conductor (and its cross-sectional area!) Incidentally, Nigel seems to think that Ohm's Law doesn't apply to his "ramps"; Ohm's Law is actually rather deeper than just 'V=IR' as underneath it all "resistance" is a process by which energy is removed from the motion of the electrons. "I=V/R" and "V=IR" as "the current that flows due to an applied voltage" as compared to the "voltage that is developed due to the flow of current" are, in fact, an aspect of Newton's Third Law. Resistance acts against current flow, whether it is viewed as "charge current" or as "energy current". Its existence completely wrecks Catt's contrapuntal capacitor. (I know that Nigel will say that Walton has "proved" that the contrapuntal flows cancel out, but undoubtedly what Walton has actually done is to demonstrate that the cancellation would be necessary, not that it happens in reality.) -- Kevin Brunt 15:06, 16 May 2006 (UTC)
- Kevin, Walton in 1980 took a 10 m long transmission line and sent 5 v pulses down it in both directions at the same time. While the pulses overlapped, there was no resistance. It is an easy experiment to do with suitable equipment. The electric drift current is induced by electric fields if the electric field exists along the length of the conductor (which it does not if the potential is a fixed 5 volts or whatever), because it forces the electrons to accelerate. (They reach a terminal velocity when resistance cancels out the acceleration, just as air resistance stops a dropped feather from accelerating endlessly.) This occurs in the ramp part of the logic step from a battery with constant voltage, or anywhere in an AC signal. But where the electric field is zero in Catt's "Anomaly" situation (i.e., 5 volts constant with respect to distance along the transmission line means E = 0 volts/metre) then any electric current must be caused by other means, such as magnetic field energy from the other conductor. The magnetic fields involve energy exchange. If I use a magnet to make a paper clip move at a distance, magnetic field energy is being delivered. Similarly, when two wires carrying currents in the same direction repel, it is due to exchange of magnetic field energy.
- This is all well established by the photon Yang-Mills theory, U(1) Standard Model electromagnetic field theory. Every occurrance of an electric or magnetic force field implies the transfer of energy ("photons" but not normal photons of light, so they are usually called gauge bosons). This was shown by Gerald ‘t Hooft and Martinus Veltman in 1970 to be the only consistent way to unify Maxwell's equations and QED, which predicts various things like the Lamb shift and magnetic moment of leptons very accurately. Nigel 82.22.34.205 16:10, 16 May 2006 (UTC)
Nigel, it would have been a major problem for physics if Walton's experiment had not shown this, as it is precisely what the standard theory predicts. However, what the standard theory says is that the "collision" of the pulses brings them to a stop. Because the "collision front" travels at the same speed as the trailing edge of each pulse, they meet halfway. At this point, the charge is compressed into half the original length of the pulse. Applying Q = C V and E = 1/2 C V², it's clear that the energy stored in the electric field has doubled, which is precisely what it should be since the charge has stopped moving, so the magnetic field has gone away and the energy that it held is exactly enough to supply the additional energy into the electric field. Furthermore, since the charge has stopped moving, the standard theory predicts that there is no loss of energy into the resistance.
On the other hand, the Catt EM/energy current theory predicts the half-width/double-voltage situation, but says that the energy is still divided between the electric and magnetic fields, so Catt had to say that 1/2 CV² must be wrong. And since the "current" is still flowing, Walton has to modify the theory so that opposing flows cancel out each other's resistance losses, at which point the whole thing is getting perilously close to 2nd Law of Thermodynamics/perpetual motion issues. -- Kevin Brunt 17:43, 16 May 2006 (UTC)
- Kevin, of course it is what the standard theory predicts. Problems with standard theory are the lack of mechanism and incompleteness, not basically a disagreement with results. Nigel 172.203.161.206 14:43, 20 May 2006 (UTC)