Interesting Paper On QFT and Quantum Measuremets

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Discussion Overview

The discussion revolves around a paper on Quantum Field Theory (QFT) and quantum measurements, with participants expressing skepticism about its legitimacy, particularly due to its acceptance of virtual particles. The conversation includes critiques of the paper's claims and methodologies, as well as reflections on the broader implications for quantum mechanics.

Discussion Character

  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants question the legitimacy of the paper, citing its acceptance of virtual particles as problematic.
  • One participant argues that the paper misrepresents the equations of motion in quantum electrodynamics (QED) and suggests that it simplifies complex concepts inaccurately.
  • Another participant notes the paper's long duration on the archive without publication or citation as indicative of its lack of credibility.
  • Concerns are raised about the paper's claim that QFT is not linear, with one participant asserting that QFT states evolve linearly in the Hilbert space.
  • Some participants express frustration over the paper's failure to adequately address entangled systems and the implications of collapse in quantum mechanics.
  • There is a sentiment among participants that the discussion has shifted from the paper itself to critiques of its content and quality.

Areas of Agreement / Disagreement

Participants generally agree that the paper is flawed and lacks credibility, but there is no consensus on specific aspects of its arguments or the implications of its claims. Multiple competing views remain regarding the nature of the issues raised by the paper.

Contextual Notes

Some participants highlight limitations in the paper's treatment of complex topics such as entanglement and the implications of virtual particles, indicating that these areas are not sufficiently addressed.

Who May Find This Useful

Readers interested in critiques of quantum field theory papers, discussions on the legitimacy of scientific claims, and the nuances of quantum mechanics may find this discussion relevant.

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I recently came across the following paper on QFT and Quantum Measurements.
https://arxiv.org/abs/1311.0205

I have read it, but it may not be legit as it seems to accept the idea of virtual particles, which I find somewhat problematic, as discussed before.

Before reaching any conclusions, I would be interested in others' views.

Thanks
Bill
 
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bhobba said:
I have read it, but it may not be legit as it seems to accept the idea of virtual particles, which I find somewhat problematic, as discussed before.
It is not legit, and I guess you already knew that. Take for example
For example, in quantum electrodynamics (QED), the Dirac field and the electromagnetic field are operators (see, eg. [11]). These operators satisfy the coupled system of equations of motion of QED. These equations can be written as follows:
Dirac eq. for phi (1)
conj. Dirac eq. for phibar (2)
Wave eq. for A_u (3)
...
Because this system of equations of motion do not permit an exact solution, it is solved approximately by the method of perturbation theory on the existing small dimensionless parameter α = 1/137 (the fine-structure constant). An important property of such a system is its non-linearity.
Despite writing "the Dirac field and the electromagnetic field are operators" the electromagnetic field is represented by its classical vector potential here. These are not "the coupled system of equations of motion of QED". Such a system doesn't exist, and certainly not in such a simple naive way. Maybe you can interpret this system as a semiclassical approximation for a single electron+EM field in vacuum. The non-linearity appears because of this approximation using the classical EM field, and especially because of the "distance measure" used to judge the accuracy of this approximation.
 
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That paper has been on the archive for 11 years without being published or cited. That alone should tell you it's crap.

The title of this thread says this is "interesting". What is interesting about "unaffiliated researcher posts some hogwash"?
 
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Vanadium 50 said:
That paper has been on the archive for 11 years without being published or cited. That alone should tell you it's crap.
The title of this thread says this is "interesting". What is interesting about "unaffiliated researcher posts some hogwash"?

That is my bad. You are correct, and apologies to everyone.

After reading your reply, I considered deleting my post, but I will leave it up as an example of being more careful.

My issue was it used virtual particles, which, of course, is just language for the Dyson perturbative expansion.

Thanks
Bill
 
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bhobba said:
My issue was it used virtual particles

It doesn't use anything! It's babble. It's not part of the scientific discussion, just something that someone managed to sneak on the arXiv. There is nothing that can reasonably discussed.
 
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The paper is obviously wrong. It says that QFT is not linear, which is wrong. The QFT state in the Hilbert space evolves linearly, as in any other quantum theory.
 
Demystifier said:
The paper is obviously wrong
Is it? Or is it obviously "not even wrong"?
 
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On any paper purporting to “solve” a particular issue in QM, I always look for their treatment of entangled systems - preferably those involving swapping. That sets a high bar, because many hypotheses won’t translate to such systems at all. Even papers that touch on entanglement simply hand wave away the obvious problems.

The cited paper doesn’t address collapse in entangled systems; they present serious problems when attempting to describe when collapse occurs and how correlations appear.
 
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I am puzzled as to why this thread is still open. What is left to discuss?
 
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Vanadium 50 said:
I am puzzled as to why this thread is still open. What is left to discuss?
We’re having more fun with the badness of the paper than we ever could have from the paper itself.
 
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  • #11
While I agree that the paper is pretty awful, it wouldn't even be in the top half on ViXra.
 
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