Talk:Ivor Catt/Archive 13
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Quantum field theory is synonymous with Theory C, and not a "pet theory"
Kevin: electrons do not touch, and electric field lines do not exist in the concept of quantum field theory for electromagnetism where all forces are due to the exchange of light speed energy (vector bosons). Doubtless quantum field theory as widely accepted now is not the full story and its maths are a fiddle as conventionally treated by the abstract spinor field theory of Lie algebra and renormalisation (see [1], and also [2]), but the numerical results and at least the very basic physical concepts (energy exchanges causing force fields) behind it have plenty of evidence. First consider what electricity is. If you charge up a x metre long transmission line to v volts, energy enters at the speed of light. When you discharge it, you (contrary to what you may expect) get a light speed pulse out of v/2 volts with a duration of 2x/c seconds, which of course implies a pulse 2x metres long. Nobody has ever proposed a mechanism where by energy travelling at light speed can magically stop when a transmission line charges up, and magically restart when it is allowed to discharge. Static electrons are therefore to be viewed as trapped electromagnetic field energy. Because there is no variation in voltage in a static charged conductor, there is no electric drift current, and no resistance or net magnetic field from current, yet energy is still going at light speed. Because it is in an equilibrium, equal amounts go in every direction possible, "reflecting" back from edges. So if you discharge from any place, you get a pulse first due to energy which already happens to be headed towards the exit point, followed by energy which is initially going the opposite way, and has to reflect before going to the exit. Because we know a lot about the electron, namely its electric charge in interactions at different energy, its spin, its magnetic dipole, we can use Heaviside's model of energy current to obtain a model for an electron: it's just a Heaviside-Poynting energy trapped in a loop by the only force that will do that, gravity. I discussed this in ten pages of articles in Electronics World, August 2002 and April 2003, which are both now cited on Google Scholar (despite the abuse from string theorists). This tells us the loop size is black-hole sized, predicting LeSage gravity right [3]. The example of the charged capacitor containing trapped light speed electricity corresponding to the amount of stored "static charge" pumped in shows that electron drift current (and hence electric current) is not vital for electric energy current. Yes, electrons drift where a magnetic field from another conductor makes them by magnetic induction, or where the electric field established in a circuit varies. Short circuit a v volt battery with a 1 metre piece of wire, and you get an electric field of v volts/metre in the wire, which causes an electric drift current. In the transmission line where you just send out a probing logic pulse, it's potential is constant after the rise portion at the front [4] so electric current there is caused by the magnetic field from the opposite conductor. Nigel 172.209.241.27 14:13, 13 March 2006 (UTC)
- Nigel does the above post follow on from an existing argument? If so which one is it? Try to use hdgs if youre changing the subject, or use existing hdgs if youre not. Thanks--Light current 16:29, 13 March 2006 (UTC)
The argument of Kevin where he says immediately above my reply: 'My quarrel with Nigel over the kinetic energy of the electrons is very closely related to this. The KE is a consequence of the motion of the electrons (ie it is related to current, and the magnetic field); Nigel ignores the concept of the electrons "touching" and so is ignoring the transmission of the forces which cause the electrons to move. This touching/transmission of force is clearly associated both with the electric fields between the electrons and (at the macroscopic level) with the applied voltage. We thus tie together voltage/current with force/motion, and end up with a description that relates the electrical concepts with mechanical equivalents. What is more, we have a description which has voltage and current simultaneously in play. Catt's Theory C deals only with the voltage steps in the TL, and Nigel's KE argument ends up with the voltage in one model and the current in another!'
For the last time, hopefully, Kevin: Theory C [Heaviside energy current without electric current] is true in the steady charged capacitor plates, where there is energy current, just like the light-speed vector boson electric field force mechanism in QFT, but without electric current. Hence electric current is not co-existent with energy current. Catt won't state his ideas clearly, or be taken seriously, because he doesn't understand this. Electric current (net drift of electrons) can only be caused by three mechanisms: (1) by voltage varying with distance along conductors, (2) by magnetic field from another conductor, or (3) by time-varying radiation reception like radio (but not automatically sine waves). Nigel 172.209.241.27 17:09, 13 March 2006 (UTC)
- LC, Nigel is running off at a tangent from Catt's theories into Nigel's own theories of the nature of the electron, which are based on Catt's idea of the electron as a "trapped" Heaviside current. -- Kevin Brunt 18:43, 13 March 2006 (UTC)
- I agree. Lets try to keep focused on Catt. THis is already the longest talk page on WP. Lets not try to make in any longer than necessary!--Light current 22:21, 13 March 2006 (UTC)
- OK Kevin. Give people time to answer these points before firing off any more posts! 8 points at a time is a bit difficult to deal with - could you keep the number of points on any one day down a bit? THanks!--Light current 22:16, 13 March 2006 (UTC)
- I've moved my text over to my own page User talk:Kevin Brunt Abstract: Catt's Theories N, H and C do not comprise the complete list. He has missed "Theory D", which is the Drude Model. This is the theory underlying the (over-)simplified "touching electrons" model. The empty conductor within which the charge of Theory N and the energy of Theory H flow is replaced in Theory D with a conductor filled with electrons, so that the conductor holds both the charge on the electrons and the energy required to bring the electrons together against their mutual repulsion. Theory D does not require that charge and/or energy traverse the conductor at the velocity of propagation; both are distributed throughout the conductor. Theory D explains everything that Theory C does, with a good deal less handwaving. I also postulate "Theory Q" in which the Drude Model is superceded by a full Quantum Mechanical treatment. -- Kevin Brunt 23:58, 13 March 2006 (UTC)
- OK THank you!--Light current 00:02, 14 March 2006 (UTC)
Refactoring this page
- Since these post and pages are now becoming so large, it may be necessary to apply immediate refactoring to reduce the volume. I would ask all contriburors to keep their posts short and sweet if possible (ie edit your own posts down to the min) to avoid enforced refactoring.--Light current 23:04, 13 March 2006 (UTC)
(Dis)agreement?
LC, if you've not visited Nigel's Feynman Gravity page, do so; search for 3.14159, and consider the following paragraph where he asserts for an expanding sphere in cartesian co-ordinates, dx=dy=dz=dr (presumably these are dx/dt, etc and r is the radius) and that therefore the rate of change in the volume is 3 times dr/dt. I will not discuss this further, but merely put it forward as a sufficient proof that Nigel and I are not going to agree at any time in the foreseeable future. -- Kevin Brunt 20:04, 14 March 2006 (UTC)
We need to get away from the physics and get back to looking at what's on the main page. Perhaps we should start with the paragraphs dealing with the dreaded "Displacement Current (and how to get rid of it)". This is certainly important since is basically what academics would describe as Catt's "master paper", since much of his later argument is built on it. In my view the current discussion of it is far too "pro-Catt", since a critical (as opposed to an uncritical) reading of the paper discloses a very serious flaw, namely that the paper simply does not present a coherent argument for its assertions about the non-existence of displacement current. The authors appear to believe that the mathematics in the appendix "prove" the assertion, but they do not explain why they think so. Without the connection between the two halves of the paper, the stepwise charging of the TL analysis is merely obfustication. It would probably be useful to try to deduce what Catt et al thought they were talking about by the term "displacement current". I believe that they were not sufficiently careful to distinguish between the basic expression of the "continuity equation", which states a relationship between current and electric field, and Maxwell's attempt to associate this with his Aether theory. -- Kevin Brunt 20:04, 14 March 2006 (UTC)
- Well I dispute the fact that the article is pro Catt- especially as I wrote most of it. I have tried to present the Catt arguments in as flat and unbiased a way as possible. Which bits do you think are biassed?--Light current 01:13, 15 March 2006 (UTC)
Differential calculus
- LC: I'll keep it short, Kevin says I say dx=dy=dz=dr means volume change is 3dr, which I don't. He says "presumably dx/dt" when this is false, I'm talking of divergence say dE(x)/dx + dE(y)/dy + dE(z)/dz = 3dE/dr for spherical symmetry where dx=dy=dx=dr. Spherical symmetry for a divergence implies that for a unit change of variable, the change in distance element is identical in any direction, hence dx=dy=dz=dr. Volume change would be the cube of the line element, not 3 times it. I'm not mentioning volume, I'm talking of divergence, and divergence is the sum of the gradients in orthagonal directions, hence the divergence for unit variable change (say unit electric field change) implies a total divergence of thrice any particular gradient, if there is spherical symmetry. Nigel 172.214.181.193 22:28, 14 March 2006 (UTC)
- On the surface of it, it seems that the differential (wrt itself) of a cubed variable is 3 times its square! is that any help?--Light current 23:30, 14 March 2006 (UTC)
- I thought that in
sphericalcartesian coords, dr = sqrt( dx^2 + dy^2 +dz^2) - as in Pythagoras theorem. So you are both wrong! Can you ignore dx^2 as being too small to matter? If so then dr=0 which is clearly wrong. Volume change is usually expressed ass the cube of the linear change but Im not sure with delta x's etc. You'd have to work it from basics. --Light current 23:20, 14 March 2006 (UTC)
- I thought that in
- LC: You and Kevin are talking about a metric, not divergence. The definition of divergence of E is: div.E = dE(x)/dx + dE(y)/dy + dE(z)/dz. For spherical symmetry, div.E = 3dE/dr, where r is the radial distance. You need this for example in getting Coulomb's law from Gauss' law (expressed as the div.E equation in Maxwell's equations). Don't let Kevin's ignorance/propaganda smear the facts with confusion. Nigel 172.202.129.237 11:06, 15 March 2006 (UTC)
LC, it's not worth arguing this with Nigel. The basic problem is that he does not realise that the partial differential Əx/Ət is fundamentally different from dx/dt, and that the identities that allow you to treat the "dx" and the "dt" as "separable" simply don't apply to a partial differential. (I am struggling to find a suitable character for the "curly d".) The only point of real relevence is that Nigel is playing with a "continuity equation", very like the one that Maxwell inserted his "displacement current" term into. -- Kevin Brunt 12:09, 15 March 2006 (UTC)
My concern with the main article is that it is phrased in a way that appears to accept Catt's position is correct. The main problem with Catt's work is that when you work out the point where he diverges from orthodoxy you will find that he has made an unwarranted assumption for which he has not provided sufficient justification. A proper "neutral point of view" needs to take one step back and distinguish between Catt's viewpoint and the article's position. In particular, the article needs to discuss where Catt's assumptions come in. For instance, he assumes that Heaviside's energy current is a "TEM" step. -- Kevin Brunt 12:09, 15 March 2006 (UTC)
LC, I've taken a copy of the paragraphs about "Displacement Current (and...)" onto my own page User Talk:Kevin Brunt and started hacking them about a bit, if you want to have a look. I've also run up some text that you might consider as a source to expand the "energy current" page. -- Kevin Brunt 01:18, 16 March 2006 (UTC)
- Nigel are you dealing with the partial differentials or the total differentials in your div calcs?--Light current 06:01, 16 March 2006 (UTC)
- LC: you can see what I'm using! Kevin, if it isn't "worth arguing with Nigel" it is because divergence is defined as I said, and has nothing to do with dx/dt. I will leave this discussion. Some of the earlier discussion with Light Current and Kevin did help a lot in clarifying the facts surrounding Catt's work, at least for me. But there is no way anything factual can get on a general Wiki science page unless it has been approved by the bigoted orthodoxy in a peer-reviewed journal and then has become popular elsewhere (off Wiki), or it will just be reverted. So all anybody can do with Wiki is to establish what the facts are by discussion on talk pages like this; you can't spread the facts widely by directly using Wiki. I'll go away now and see if I can write a clearer paper explaining the constructive uses of Catt's ideas. Thanks, nigel172.212.222.123 10:52, 16 March 2006 (UTC)
- Not neccessarily! You may have had difficulty producing curly ds. I assume your answer maens you are considering the total differential and not the partial.--Light current 23:08, 16 March 2006 (UTC)
Mass continuity equation
The derivation of the mass continuity equation can be seen here [5]; the page also links to an overview of the derivation of the divergence. In both cases it can been seen that Nigel uses "ordinary d's" where he should be using the "curly d's" of the partial differential equation notation. The important point to note on the page I reference is the statement This holds for an arbitrary volume and so must be true at each point in space. This statement is equally true for both Maxwell's Equations and the Telegrapher's Equations. In particular, the Telegrapher's Equations are derived from the partial differential equations that describe the behaviour in three dimensions of the infinitesimal inductance and capacitance of a point. The Catt, Walton and Davidson stepwise charging TL due to finite propagation times does not break orthodox electromagnetism because they are using a set of equations that already have it all built-in. -- Kevin Brunt 13:01, 16 March 2006 (UTC)
- Messsage to both Nigel and Kevin. Please remain calm. I would ask each of you to read again each others previous posts on this subject to see where the (mutual) misunderstnading may lie. I have not been following the discussion closely so cannot help directly.--Light current 23:17, 16 March 2006 (UTC)
Light Current - this isn't a misunderstanding that can be cleared up by further analysis; it is a basic disagreement about how science is done. Nigel has written down the "mass continuity equation" using the "wrong sort of d". Either it is a font problem, or Nigel is using a different equation entirely, or he simply doesn't what the difference in the notation means. Either way there is a problem, but Nigel doesn't want to answer questions about it. The real issue is that if he understood how science is done, he would expect people to ask questions. Science is all about asking questions. Nigel appears to believe that because he can write down a sequence of mathematical symbols that eventually arrives at a plausible number, that he has "proved" his theory correct. This is simply not so. He has to be able to justify the whole of his argument, and every assertion and mathematical operation that he uses. And this means answering the questions. -- Kevin Brunt 18:45, 17 March 2006 (UTC)
Nigel seems to follow the example of Catt, who clearly who thinks that the sort of simplistic "walk-throughs that appeared in the textbook that I used for O-Level Physics constitutes a full proof of the theory. The real proof lies in the experimental work that was done to show that the hypothesis-under-test was the only one that came up with the right answers all the time. -- Kevin Brunt 18:45, 17 March 2006 (UTC)
- Kevin, I've written my paper, so I'm back. What awkward question? That you want me to explain calculus to you? I state facts here without talking about divergence, then you go off to my home page and claim you take issue with the symbolism on something else. Then you show you don't know that divergence is the sum of the gradients in three perpendicular directions (hence the total divergence for spherical symmetry is thrice the gradient in any given radial direction), then you take issue with a symbol. Go read a book on calculus or take a course in it. In calculus the meaning of say dE/dr is that dE symbols the variation produced in the value of E when r increases by the infinitesimal amount dr. Delta E or ƏE is a small not not infinitesimal increase in E. ƏE/Ər -> dE/dr when the size of Ər falls towards zero (becoming infinitesimal). In most physical situations, d can be replaced by the more approximate Ə in differential equations, allowing numerical solution if you can't analytically solve the formula. Again, nothing you are saying about divergences or Ə and d symbolish relates to Catt.
- The fact Kevin writes this drivel, just shows the poverty of the critics of Catt et al. When Kevin exposed his ignorance of divergence I was polite. But he later launches into a personal attack based on false permises: if I don't need to use particular symbols or whatever, this does not imply I'm ignorant. See comments on [6] for the tactics of mainstream philistines. When they lose, they make personal remarks based on their own ignorance about others. This para is a defence against the prevailing climate, which is to find false reasons to dismiss facts. Nigel 172.214.149.87 18:48, 17 March 2006 (UTC)
- I must reiterate my request for all concerned to remain calm and civil to those who may know less than you do on certain subjects. Patient explanation is the way to win allies.--Light current 22:23, 17 March 2006 (UTC)
Admonishment
Nigel, I invite you to strike out your last para with the personal attacks on Kevin.--Light current 22:34, 17 March 2006 (UTC)
- I've removed the strong wording. Nigel 172.201.115.187 09:50, 18 March 2006 (UTC)
Thanks Nigel. I appreciate it. However accusing Kevin of writing 'drivel' (even tho you may think so) is still pretty offensive!--Light current 17:34, 18 March 2006 (UTC)
- Nigel, I did "Maths for Chemists" as a mandatory half-unit of the 1st year of BSc Chemistry, which included partial differentials. I will not pretend to remember very much of it, since I've not used any of it anger in 30 years, but I do know that "delta x", "d x" and "curly-d x" are distinct. Have a look at partial_differential_equations -- Kevin Brunt 19:44, 17 March 2006 (UTC)
I certainly agree that they are distinct. Nigel knows this Im sure, but I feel he may have taken a few shortcuts in his maths that we must now ask him kindly to explain in simple terms!--Light current 22:19, 17 March 2006 (UTC)
- Maxwell's Equations and the Telegrapher's Equations are partial differential equations. Catt, Walton & Davidson's rejection of the Laplace transform is a denial of the partial differential equations on which the theory of electricity is built. The "lumped capacitor" which Catt so frequently decries is merely a massive simplification so that engineers can do simple electrical circuits without having to know calculus... -- Kevin Brunt 19:53, 17 March 2006 (UTC)
Further explanation by Nigel on difference between straight and curly d's
Kevin and LC: the distinction of curly and straight d's is important mathematically, but less so physically in most situations. I can't think of any situation where the accuracy is so good in physics than there is a difference. In most of quantum mechanics, you can't get exact results anyway to the differential equations, so you solve numerically. Even if I had used wrong symbols in this case, it wouldn't affect the physics, only the maths. Kevin is also making a vacuous claim that the details are of concern to referees, when it is not possible to get anything outside the mainstream paradigm read at all due to string theory [7]. This is exactly the issue Ivor Catt came up against. People don't read his papers carefully and find mathematical errors and use that to censor him. He has been very open in publishing the reasons why he has been censored: the physical interpretation. Simplifications of the facts are by definition wrong in detail, so it's significant that Kevin is defending the simplification used in lumped capacitance by the mainstream as being justified, while trying to erroneously attack innovation for using a more accurate model! Nigel 172.201.115.187 10:04, 18 March 2006 (UTC)
Kevins reply to Nigel
Nigel, your latest comment strongly suggests that you are still thinking of the partial differential notation as some sort of "approximation". Is this your own idea, or something that you've caught off Catt? What partial differentials are about is the generalisation of the differential calculus into situations where there is more than one independent variable. Thus in your Əρ/Ət, ρ is actually ρ(x,y,z,t) - the density at the (arbitrary) point (x,y,z) at time t. Əρ/Ət is then another function of x,y,z and t, which describes how the density changes wrt time at any given point. This is a partial differential, because there also Əρ/Əx, Əρ/Əy and Əρ/Əz, which you would use to map spatial inhomogeneity of the density. -- Kevin Brunt 21:26, 18 March 2006 (UTC)
You cannot separate the physics from the maths. When mathematics appears in a physics paper, it is being used to describe the physics. An error in the mathematics is an error in the physics, and if there's an error in the one, it invalidates the other. Consider Catt's Mar 1980 Wireless World article; it contains a error of "schoolboy howler" magnitude and would certainly not have got past any peer-review process. Goodness knows why Catt was still pushing it in 2004. Basically he has botched his co-ordinate systems, so that when he asserts that dx/dt is positive he is looking at the motion of the train relative to the observer rather than vice versa. Rather than every mathematician since Newton being wrong, Catt is! You can do this with all of Catt's work. When he diverges from orthodoxy you will find that he has made an unwarranted assumption or an assertion that is not founded on secure fact. It is the job of peer review to make sure that authors show their workings properly. That the process does not always operate perfectly is not a case for discarding it altogether; Catt's difficulties lie not with the review process but with the inadequacies of his articles, as they almosyt invariably fail to justify their premises. -- Kevin Brunt 21:26, 18 March 2006 (UTC)
As for the "simplification". I am not arguing for or against. Catt is arguing against the "lumped capacitor" (which reduces ƏV/Ət for the capacitor to dVdt, and thus deriving Q=CV, by assuming that the charge is spread evenly across the capacitor). However, he is then using another simplification which considers a capacitor as a one-dimensional conductor. Much of the rest of the muddle of Catt's electromagnetism derives from his failure to acknowledge that he is using a simplification, as by using a mathematical model of a transmission line in terms of the impedance at its ends, and voltage steps propagating along the TL, he does not appreciate that the current doesn't "reflect" at the open-end of the TL in the same way as the voltage. Since the flow of energy (ie power) is voltage times current, the fact that the voltage and current do not reflect "in phase" means that the energy also does not reflect in phase, which invalidates the basic premise underlying Catt's contrapuntal energy currents entirely. -- Kevin Brunt 21:26, 18 March 2006 (UTC)
- Kevin, the paragraphs above you conflict what you were saying before. You defended the fatally flawed lumped capacitance model as being a helpful simplification for calculations. Now you say "You cannot separate the physics from the maths." This is wrong, because maths is fundamentally an approximate quantitative representation of reality: Newton's laws are only approximate (general relativity is more accurate, but still has problems with cosmology, and quantum gravity officially doesn't exist). Hence, the physics of reality is something which is not achieved in today's mathematical models. I'm not going over the errors in Maxwell's classical electrodynamics again as we've been there already in detail. The point is, you're just plain wrong: the physics is today distinct from the maths we have. This remains until there is a mathematical unification of classical and quantum theories. Nigel 172.212.37.174 13:53, 20 March 2006 (UTC)
Nigel, the lumped capacitance model is a simplified model of the physics of a capacitor, where the capacitance is treated as existing at a point, rather than being distributed over a plane. This simplification of the physical model means that it is not necessary to consider how the charge spreads across the plane. This simplified physical model is described by simpler mathematical equations. The mathematics have not be simplified; the physics have been simplified, and the mathematics, being tied to the physics, necessarily follows suit. The mathematics precisely describes the physical model; it is the physical model which is only an approximation to reality. Note that any model of reality is approximate, because we can't measure reality absolutely precisely in the first place. -- Kevin Brunt 19:28, 20 March 2006 (UTC)
- Kevin, you've ignored what I said: the maths changes, for example, GR is different from Newton's law of gravity. GR says the Earth's radius is contracted by 1.5 mm, that light passing the sun is deflected by twice the amount given by Newton's law (which applies to slow moving objects), etc. The physics is real, but the maths alters as discoveries occur. By using bold type to link physics to maths, or by shouting, you may convince those with weak minds to obey your decree. But the fact remains: mathematical models are not physically correct just because they have been fiddled/created to approximate some measured data. Introducing Heisenberg's uncertainty principle doesn't alter this, it just means that you measure statistics. You don't need absolute precision to do science. Einstein didn't need to measure anything precisely to introduce GR, just a logical argument. Nigel 172.212.230.193 10:30, 24 March 2006 (UTC)
If the lumped capacitance model is flawed, the Catt "capacitor is a transmission line" model is equally so. The lumped model described the plate of a capacitor as a zero-dimensional point. The Catt model describes it as a one-dimensional line. The plate is really a two-dimensional surface. Let us re-examine the Catt model starting with a square plate, with the connection at a corner. It should be clear that to describe this using the Catt, Walton and Davidson method, you have to use a model with not one transmission line, but a whole series of transmission lines radiating out from the corner. Each of these lines will have a different length, so that the reflected voltage steps will return to the input end at different times, and will then propagate back out along all the lines. Thus we have not one step, but many, which multiply with each out-and-back step on each line. Each step is also of much less amplitude, so the stepwise nature of the voltage waveform is much reduced both in voltage and in time. This is emphasised when you "take the limit" of an infinite number of transmission lines, when the returning step is transformed into a ramp. The situation becomes even more complex when you then move on to consider the 2-d surface properly and had to consider whether the "reflected edge" actually travels back in the reverse direction, rather than spreading across the plate. It would seem that the lumped capacitance model may actually be a closer approximation to what is actually observed than the Catt model... -- Kevin Brunt 19:28, 20 March 2006 (UTC)
- The model described by Catt for his TL cap is treated as a one-dimensional line. A capacitor plate (whether circular or rectangular) is a two-dimensional surface that can be treated as a number of TLs in //. No problemo!--Light current 00:54, 21 March 2006 (UTC)
Let us re-examine the Catt model starting with a square plate, with the connection at a corner. It should be clear that to describe this using the Catt, Walton and Davidson method, you have to use a model with not one transmission line, but a whole series of transmission lines radiating out from the corner. Each of these lines will have a different length, so that the reflected voltage steps will return to the input end at different times, and will then propagate back out along all the lines. Thus we have not one step, but many, which multiply with each out-and-back step on each line. Each step is also of much less amplitude, so the stepwise nature of the voltage waveform is much reduced both in voltage and in time. This is emphasised when you "take the limit" of an infinite number of transmission lines, when the returning step is transformed into a ramp.
- I must take issue with your analysis here Kevin.
- First off, Catts cap plates are not square, thay are rectangular.
- Second, they are assumed (as I assume) to be fed from a transmission line of correct proportions such that there are no reflections at the interface.(ie tapering lines, impedance transformers etc betweeen the line and capacitor.)
- Your supposition that things in a practical circuit are not ideal I think is correct. However, this does not,IMO, invalidate Catts analysis of the capacitor acting as a TL, which I believe to be correct. If there is any doubt about how TLs or capacitors charge up, its so easy to do the experiment yourself!--Light current 00:54, 21 March 2006 (UTC)
LC, it will save a lot of argument if you would review the Dec78 Catt et al paper that I'm working against. This paper very specifically models a capacitor of the form of a sector of a circular plate fed at the point as a TL, with the source impedance explicitly much greater than that of the TL. I am positing the "squaring off" of the curve, so that the distance from the point of feed to the outer edge varies depending on the direction. The issue is not that a TL charges up stepwise, it is that in many ways the 1D "TL model" is less useful than the 0D "lumped capacitance model" as a description of the way that charge distributes on the 2D surface of the plate of a capacitor. What, indeed, are the characteristic impedance and velocity of propagation of a 4700μF electrolytic capacitor and how long is it? -- Kevin Brunt 01:37, 21 March 2006 (UTC)
- I'm familiar with the article. I dont think your argument regarding angles is atall relevant to Catts analysis which in my view is substantially correct. If there is a mismatch between the feed and the Z0 of the cap, you get reflections. Whats the problem? BTW a capacitor is sometimes made from separated plates wound ito a cylinder. They are all transmission lines!--Light current 01:57, 21 March 2006 (UTC)
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