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#21
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| Bilge wrote: It seems that you just need to turn a couple of pages and read about "simultaneous measurability" of observables in classical and quantum mechanics in subsections 3.2.3 and 3.2.4. Thanks for the grammar correction. I'll fix that. Obviously, I This simply means that if I prepare an ensemble of systems in the state |j,j_z> and measure observable j_x in these systems, I will not obtain a fixed value. Each measurement will yield a different value. These measured values will be distributed according to the (square of the) wave function which state |j,j_z> has in the j_x representation. I agree with you completely. If you turn a couple more pages (page 14 of chapter 3), you will find discussion of similar unpredictability in pinhole camera and radioactive decay. I am not talking about general relativity. I am talking about special relativity. I gave you references to Bjorken and Drell, and Weinberg. They demonstrate relativistic invariance (Poincare commutators) of QED in the Coulomb gauge (you can find the details of the proof in subsection 11.1.3 of my book). They use interaction in both Hamiltonian and boost operator. This proves my point. Now it is your turn. Stop hand-waving and show me a proof, or at least a reference, of relativistic invariance of QED in which boost operators remain non-interacting. Eugene. |
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#22
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| Bilge wrote: [...] I think you should read again about the difference between measurement (single act of observation, see subsection 3.2.1) and experiment (many measurements performed on identically prepared systems, or ensemble, see subsection 3.2.2). Measurement always yields a certain value which can be made as precise as we want. Experiment yields a certain value of observable only in the case when the system was prepared in an eigenstate of this observable. If the system is not in the eigenstate, then different measurement (comprising the experiment) will give different values. The frequencies of these values will be distributed according to the (square of the) wave function of the state. That's basic quantum mechanics, and we must agree here before moving further. Eugene. |
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#23
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| Eugene Stefanovich <[Only registered users see links. ]> wrote in message news:<[Only registered users see links. ]>... [...] (1) (2) (3) (1) and (3) are certainly controversial, (3) especially so. GR was (in part) developed to eliminate instanteous gravitational interactions. It's principles are highly respected, I would certainly suggest you understand what you're doing before taking a hard stand ...I also noted you've used "Dr. Flandern" as a reference, that is risky in the GR community, again very controversial. Well the good thing is, you've consolidated your thinking circa 2004. However (employing military analogy) I won't advise attacking on 3 front's simultaneously in one book, is a trilogy possible? Minkowski spacetime was "adulterated" by Einstein as an introduction to GR, the introductions written about his spacetime in textbooks are a simplified version. In that epoch, tensor analysis applied to dynamic systems was at it's infancy, and crude approximations from that time are often presented as the holy truth, just old habits. Certainly, but only on parts I can effectively comment on, but I'll do that anyway. You might present the conventional stand point clear and crisp, but point out the defects, many of which are standard in the literature, that's a good thing, then reference to an appendix for your own point of view. Yes and to your credit the're peer reviewed. GR is more about "covariant" equations of motion than merely a theory of gravity. To merge quantum theory and relativity it's easier (imo) to place QT on GR, then at least you start with a covariant foundation for QT. You may want to place the "detail" in an appendix. Well the ambition of your program verifies that! I think it's experience. When I was a teacher it sharpened me up doing lectures, mind if you tell us how old you are? Won't have noticed, your grammar skills are superior to mine. Ken S. Tucker |
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#24
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| > Muons are the proof that relativity is hopelessly wrong. Okay let's see, Let's figure the muon's average lifetime is 2.2 x 10-6 s in its own rest frame; therefore that is the proper time. We want to find the time in the moving rest frame, (v2 = 0.998c) Dt = Dt0 / (1 - v2/c2)1/2 = 2.2 x 10-6 s / [1 - (0.998)^2]1/2 = 35 x 10-6 s or roughly 35 microseconds. Here is how far it will travel in that time. x = vDt = 0.998 x 3 x 108 m/s x 35 x 10-6 s = 1.0 x 10^4 m = 10000m or roughly 6 miles. I am not sure where you get 50,000m as muons are produced closer to the surface than that. As far as I can tell there is no need to supercede the speed of light. |
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#25
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| Ken S. Tucker wrote: GR has nothing to do with this. For systems I am considering, gravity can be safely neglected. I wrote this book not to please some community, but to find the truth. So, I don't care about controversies. All issues are closely related to each other. So, I see more sense in putting them together. Do you believe in Minkowski spacetime in the absence of gravitaion or not? I can formulate my position even stronger: I am against unification of space and time in one 4D continuum and against covariant (tensorial) transformation of observables. However, I do not want to discuss gravity here. I am not ready to do that yet. Thanks. My disagreement with the conventional stand point is too profound to put it in appendix. You may notice that manifest covariance is formulated as Assertion F in Chapter 1. This means that this assertion is proven wrong in my theory (see, e.g., section 12.3). I do care about relativistic invariance, though (the difference with manifest or Lorentz covariance is explained on page 27 in chapter 12), i.e., equivalence of all inertial observers, which is mathematically expressed in commutation relations of the Poincare Lie algebra. I am 43. You can find my brief CV on [Only registered users see links. ] Thanks. |
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#26
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| Ken S. Tucker wrote: This is the essence of my approach to relativity that (1) and (3) are NOT controversial. Even with instantaneous interaction, there is no "grandfather paradox" in my approach, because I use interaction-dependent boost transformations to describe moving observers. Please take a look in subsection 12.3.3. Eugene. |
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#27
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| Eugene Stefanovich: Well, even there, you give the impression that the indeterminism of quantum mechanics is somehow less desirable or missing some physics compared with a deterministic theory like classical mechanics. However, I would argue that the inherent indeterminacy contains the real physics. The uncertainty principle (which is just a different way to state the uncertainty relations), is the reason one can quantize things. Also, the indeterminacy doesn't mean ``unpredictable''. Deterministic systems are usually unpredictable, however. Quantum mechanics is ergodic. Classical systems are chaotic. Quantum mechanics places a finite limit on entropy. Classical mechanics requires an infinite amount of information to specify a system. Probabilistic systems are stable. Classical systems are not. My impression of what I read was that the indeterminacy in quantum mechanics was not a feature of the theory but the reason to look for a deterministic alternative. I'm a little vocal about this particular aspect, because of the vast number of misconceptions that make people think quantum mechanics makes no sense or that there is something magic about it. [...] Well, you apparently think that, but what else do you call an interaction that modifies spacetime in a non-linear way? Most people call that general relativity. The only difference is most people associate spacetime curvature with mass. You've turned the ``curvature'' in E&M, which is not a curvature of spacetime, into a curvature of spacetime. Your theory is not QED. You've gone to a lot of effort to make that point. They don't modify the lorentz transforms, since their lorentz group is the same as the homogeneous poincare group. If you post the derivation, I'm fairly sure I know exactly where to find the difference. It doesn't prove your point. You post a proof. You are making the claims and you have the textbook handy. How long can it be? The entire qed lagrangian can be derived in a page or two, depending upon how many words you use. I have no doubt weinberg proves what you say about the hamiltonian he uses. I just want to see it so I can find the point at which you and he diverge. I'm going to bet that the difference is that he uses the canonical momentum which you also found reasom to object to using. If the potentials change your lorentz transforms, then using a.p rather than a.(p-eA) would be a good reason for that. |
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#28
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| "Eugene Stefanovich" <[Only registered users see links. ]> wrote in message news:[Only registered users see links. ]... in space-time times, [Only registered users see links. ]. The point however is it is assumed that the interaction occurs in a flat space-time background to which the above assumptions apply. If you are attacking that assumption then I agree SR may have a case to answer (and answered in GR). I may be mistaken in your views but my reading of them is the above is not the assumption your are attacking. For example look at classical mechanics (eg Landau - Mechanics). In analyzing particles in a classical gravitational field it is assumed such a field is superimposed on an inertial frame even though its existence breaks isotropy. Thanks Bill |
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#29
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| Bilge wrote: I do not disagree with you here. My own views on quantum mechanics are best explained in subsection 3.3.3, especially in the quote from Einstein in the end if this subsection. Independent on our philosophical views, I suggest to follow Feynman's advice "Shut up and calcuilate!" Where did you find spacetime and its curvature in my book? There is not a word about it! Forget about spacetime. Think about observables of particles, like position and momentum. It's much more productive. Take a look in subsection 11.1.3. There is a full derivation of Poincare commutation relations in QED (borrowed and expanded from Weinberg's paper). My point is that in QED both Hamiltonian and boost operator contain interaction terms (see subsection 11.1.2). Only in this case Poincare commutation relations are satisfied. This is what Weinberg, Bjorken, Drell, Schwinger, and many others explicitly demonstrated. Again, the proof of relativistic invariance is in subsection 11.1.3. I do not provide the derivation of QED Hamiltonian in the Coulomb gauge used there. You can find it, for example, in Weinberg's book. Eugene. |
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#30
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| Bill Hobba wrote: Let us forget about "space-time background". I do not know what this means exactly. Let us speak about observable things - positions of particles which are expectation values of their position operators. We have observer O which observes that particle A has position x_A and particle B has position x_B. Now, the question is about position measurements by moving observer O'. Your line of reasoning is this: For particle A all directions in space are equivalent. From this you derive Lorentz transformations. I.e., you obtain that for observer O' the measured value of position of particle A can be obtained from x_A by using some universal formula independent on where the particle B is. I say, that all directions in space are not equivalent for A, because there is particle B sticking around, and you cannot disregard that. I don't know what this particle is doing there. Maybe it is "curving the space-time" or whatever. But this particle is there, and certainly destroys the symmetry of the neighborhood. My point is that you cannot pretend that all directions in space ate equivalent for particle A. Therefore your derivation of Lorentz transformations for the position of A fails. Correct transformation must take into account the presence of B and depend on the stregth of inrteraction between A and B (if A and B interact, of course). In my book, I do not derive boost transformations in this way. I do my derivation in subsections 7.3.6 and 7.3.7 for one free particle. The transformations for many-particle systems are discussed in 12.3.1 and 12.3.3. GR has nothing to do with it, because GR uses the same SR idea of universal space-time, only curved. Please understand me, I am not trying to say that EM interactions curve space-time. I do not want to talk in terms of space-time at all. I want to talk in terms of particle observables (positions, momenta, spins). I do not care what kind of space-time is behind these observables, or if there is any space-time at all. I don't have this book with me now. But I remember they used homogeneity-isotropy argument to derive action for one free particle. (is it what you are talking about?) I have no objections to that. And indeed, in my approach, boost transformations of position for one free particle are consistent with Lorentz transformations (see 7.3.6 and 7.3.7) Eugene. |
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