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The wave packet description 
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#55
Nov2206, 04:09 AM

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For a quantumlike interpretation of classical mechanics see also http://arxiv.org/abs/quantph/0505143 


#56
Nov2206, 04:14 AM

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#57
Nov2206, 06:39 AM

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#58
Nov2206, 09:36 AM

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PF Gold
P: 6,236

My impression is that it is indeed possible to generate lorentzinvariant trajectories (that's the entire crux) for free scalar particles, because in that case, indeed, there's nothing that really needs to be transmitted superluminally. I should take a deeper look to see if interactions, which have a genuine superluminal effect in BM, can also be formulated in a lorentz invariant way, as I was under the impression that this was impossible. That is, are there still lorentzinvariant world lines (which are the same, no matter in what reference frame they have been obtained) of Bohmian particles, when we consider interactions ? If that's really the case (and I thought it was genuinly impossible), then this makes BM way way more attractive. But I doubt it. 


#59
Nov2206, 10:29 AM

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#60
Nov2206, 10:49 AM

P: 72

In particular, you didn't understand, so called, second quantization. In the introduction you notice that the object that satisfies KleinGordon equation is not a wave function but a field operator. However, in the third section you call it a wave function anyway and even worse you introduce in eq. 3 a third quantized operator on the right hand side. Do you realize that? The left hand side of eq. 3, \psi, is already a "second quantized" operator and to get a wave function for a Fock state n> you should have put \psi in place of \hat \phi in the RHS! As to you remark on BM, I see you agree that it is a useless curiosity at best as far as QM is concerned. The domain of your objection is relativistic QM. But even there how do you pick initial conditions for the Bohmian trajectories (defined correctly i.e. not as you did it)? Don't you have to draw them from some probability density? If the answer is afirmative then you have your "statistical transparency". To sumarize, the eprint has nothing in it. Cheers! 


#61
Nov2206, 12:07 PM

P: 3,408

One of myriad descriptions of the wavepacket might be as a probabilistic representation of an entity's complementary measurements excluded from each other by the magnitude of Planck's constant.



#62
Nov2306, 05:15 AM

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#63
Nov2306, 07:09 AM

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Nice answer to a detailed argument, too. Cheers! 


#64
Nov2306, 07:41 AM

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#65
Nov2306, 09:25 AM

P: 451

ueit:"In a double slit experiment it's the wall with the slits. An electron passing near such an object changes momentum. The mechanism behind this change is ignored so we shouldn't expect a good prediction of the individual detection event. So, besides the probable statistical character of the wavefunction itself, we have another approximation regarding the potential at the slits (which is assumed to be 0 although it's only 0 on average)."
You did not answer my question: Do you agree that lossless beamsplitter is real life realization of the "wall"? 


#66
Nov2306, 10:14 AM

P: 451

Zbyszek:” I don't think there has been much progress since Einstein. If anything it would be rather a regress. These days Bohr is perceived (unjustly again) as a winner of the duel with Einstein over the meaning of QM. So, not many guys are even aware that we are still missing a quantum theory of single objects and that QM is incomplete indeed.”
You are kidding. I am asking seriously. For example, investigations of R.J. Glauber and others established the connection between classical and quantum statistical mechanics. On the other side, the single particle approach also led to enormous progress in QT: QED, local gauge abelian and nonabelian interactions, electroweak unification, quarks, QCD, etc. However, in that game the role of “interpretations” is not clear. Looks like something stand alone. May you present coherently what is the content of the “normal physicist” criticism of the standard approach to QM? 


#67
Nov2306, 11:01 AM

P: 1,667

QFT has no realistic, local single event interpretation, period (and mind MWI is not realistic). 


#68
Nov2306, 11:35 AM

P: 451

Careful:"QFT has no realistic, local single event interpretation, period (and mind MWI is not realistic)."
I agree. I claim that nonrelativistic QM is complete. I don't claim that QFT is complete. And this is not a question. We discuss the description of the statistical ensembles in terms of wave packets. 


#69
Nov2306, 11:48 AM

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#70
Nov2306, 12:20 PM

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(meaning: where events really, and uniquely, happen) 


#71
Nov2306, 12:26 PM

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#72
Nov2306, 03:15 PM

P: 379




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