A Superluminal Signalling proposal in peer-reviewed journal

[Pelion]

Hi to all,
A proposal of mine, that purports to enable faster-than-light communication, has been accepted (a few months ago) by an esteemed peer-reviewed physics journal: Pramana, Indian Academy of Sciences. The article will appear in January. The PDF of the accepted version is attached.

<comments to moderators deleted>

 

[Dale]

an esteemed peer-reviewed physics journal: Pramana, Indian Academy of Sciences

Pramana is hardly "esteemed" the impact factor is about 0.5 I had never even heard of it until you brought it to my attention.

From your paper "the possibility of constructing superluminal signaling protocols within the context of
non-relativistic quantum mechanics". The compatibility of superluminal signaling with non-relativistic quantum mechanics is not in doubt, but relativistic quantum mechanics (QFT) is incomopatible with superluminal signaling. It is QFT that is consistent with experiment.

 

[atyy]

From p6 of the paper: "In addition to being non-standard, we must also stress that expression (5) was posited solely on the heuristic notion of quantum mechanical ‘indistinguishability’ and, therefore, it remains to be seen if this state-vector transformation is allowed by quantum optics (implying that there would have to exist latent elements in the Fock-space algebra that go beyond the standard Hilbert-space formalism)."

I haven't thought through in detail, but I think the indistiguishability argument is wrong. Rather than a superposition, one should get a mixture.

 

[Pelion]

Pramana is hardly "esteemed" the impact factor is about 0.5 I had never even heard of it until you brought it to my attention.

From your paper "the possibility of constructing superluminal signaling protocols within the context of
non-relativistic quantum mechanics". The compatibility of superluminal signaling with non-relativistic quantum mechanics is not in doubt, but relativistic quantum mechanics (QFT) is incomopatible with superluminal signaling. It is QFT that is consistent with experiment.

...then the Indian Academy of Sciences is not esteemed in your opinion and, apparently, you have not perused the journal...if you had, you would see highly mathematical and complex works, replete with articles in topics like supersymmetry and quantum chromodynamics. How great for a senior member of a physics journal to attack a peer-reviewed journal because he doesn't like the paper published by it! There are many esteemed peer-reviewed journals with small impact factors (eg, Foundations of Physics, Physica Scripta, Phil. of Science,). The higher-impact-factor journals many times will simply not take a chance on a controversial paper. I sent the article to three journals and used the exact same 'suggested referee' list, but it was only Pramana that proceeded with peer-review...so, regardless of what your opinion is, my paper was very likely reviewed by the people I suggested ( Alain Aspect, Nicolas Gisin, Guang Can Guo, Dipankar Home, Jian Wei Pan)...all well known experts in the topics involved. This work sprung up from a long and rich discussion and debate with several physicists (including Ruth Kastner, John Cramer, Nick Herbert, Martin Suda)

 

[Pelion]

...then the Indian Academy of Sciences is not esteemed in your opinion and, apparently, you have not perused the journal...if you had, you would see highly mathematical and complex works, replete with articles in topics like supersymmetry and quantum chromodynamics. How great for a senior member of a physics journal to attack a peer-reviewed journal because he doesn't like the paper published by it! There are many esteemed peer-reviewed journals with small impact factors (eg, Foundations of Physics, Physica Scripta, Phil. of Science,). The higher-impact-factor journals many times will simply not take a chance on a controversial paper. I sent the article to three journals and used the exact same 'suggested referee' list, but it was only Pramana that proceeded with peer-review...so, regardless of what your opinion is, my paper was very likely reviewed by the people I suggested ( Alain Aspect, Nicolas Gisin, Guang Can Guo, Dipankar Home, Jian Wei Pan)...all well known experts in the topics involved. This work sprung up from a long and rich discussion and debate with several physicists (including Ruth Kastner, John Cramer, Nick Herbert, Martin Suda)

...oh, by the way, this paper went through TWO rounds of review with Pramana, because of its controversial nature...so it went through more extensive review than is typical.

 

[Nugatory]

...oh, by the way, this paper went through TWO rounds of review with Pramana, because of its controversial nature...so it went through more extensive review than is typical.

As indeed it should have. Just as extraordinary experimental results require extraordinary evidence, extraordinary theoretical results require more than the usual level of skeptical scrutiny.

It would be interesting to know what issues were raised during the peer review, and what revisions to the paper resulted.

 

[Pelion]

As indeed it should have. Just as extraordinary experimental results require ex:traordinary evidence, extraordinary theoretical results require more than the usual level of skeptical scrutiny.

It would be interesting to know what issues were raised during the peer review, and what revisions to the paper resulted.

Yes, good point.
The issues raised:
Eq.5 embodies a non-unitary transformation and relies on heuristics, thus it is not clear (at this point) if the application of the full quantum-optical description of the scenario will refute or support the import of Eq.5. Note: one reviewer did stress, however, that this is an 'intriguing question'. Two reviewers raised this concern, and I had to explicitly state that Eq.5 is non-standard and results from heuristics (text immediately following Eq.5 in the paper).

Supposed contradiction in logical structure (second round of review): one (the third) reviewer argued that the scheme is logically flawed because neither the left or right wing of the setup is a 'preferred measurement reference' and thus it should not matter on what wing the measurements occur, while my scheme implies different composite (entangled) states depending on whether the measurement occurs on the left or right wing of the setup. My response was that my scheme implies an absolute reference wrt the composite quantum state: whatever wing (left or right) locally collapses (measures) the state first determines the form of the composite quantum state; the left and right wings of the setup are asymmetrical and require different measurement configurations, resulting in different final states and, furthermore, the local measurement that happens 'first' decides between the alternative states. I did not have to make any revisions regarding this reviewer's argument.

 

[PeterDonis]

whatever wing (left or right) locally collapses (measures) the state first determines the form of the composite quantum state

This is obviously inconsistent with QFT, since QFT requires operators at spacelike separated events to commute. I note that your analysis of the experiment does not use QFT at all; it uses non-relativistic QM (which is problematic in itself since the experiment is dealing with photons). Has anyone attempted to analyze this experiment using QFT? I would expect the prediction of QFT for the outcome to be different from yours.

 

[Pelion]

This is obviously inconsistent with QFT, since QFT requires operators at spacelike separated events to commute. I note that your analysis of the experiment does not use QFT at all; it uses non-relativistic QM (which is problematic in itself since the experiment is dealing with photons). Has anyone attempted to analyze this experiment using QFT? I would expect the prediction of QFT for the outcome to be different from yours.

...the only reason that QFT 'requires' that spacelike-separated observables commute is because this was 'built in' from the start, by fiat, as a presumed axiom...it is called 'microcausality' and is not derived from first principles. So, in this case, experiment would be the best test (provided of course this proposal is serious enough to warrant empirical verification and is not trivially flawed).

 

[martinbn]

What about a coincidence counting?

 

[PeterDonis]

the only reason that QFT 'requires' that spacelike-separated observables commute is because this was 'built in' from the start, by fiat, as a presumed axiom

This is beside the point; I was only pointing out that, given that this is a property of QFT, the QFT prediction for the outcome of your proposed experiment must be different from yours. (I suppose it should also be pointed out that this property of QFT has lots of experimental support; it wasn't just pulled from thin air.)

experiment would be the best test

If you have two theories that make different predictions for the outcome of an experiment, then yes, doing the experiment will distinguish between those two theories. (It might show that both are wrong, but it can only show that at most one is right.)

However, I'm not sure that you have an actual theory of your own; you appear to be attempting to use ordinary QM in your analysis. But we know that ordinary QM is not exactly correct; it's a non-relativistic approximation to QFT. (When I say "know" here, I mean we have tested this experimentally; we have done experiments whose results match QFT and not ordinary QM.) So it seems obvious that someone should analyze your proposed experiment using QFT to see what it predicts.

If indeed you are trying to propose an alternate theory, which is not either ordinary non-relativistic QM or QFT, and using it to predict the outcome of your proposed experiment, then it seems to me that your presentation of this alternate theory is extremely sketchy.

 

[Dale]

then the Indian Academy of Sciences is not esteemed in your opinion and, apparently, you have not perused the journal.

That is not only my opinion. The impact factor of 0.5 indicates that the entire scientific community does not think highly of a journal. Certainly your characterization of “esteemed” is not representative of the scientific community’s opinion. Factually, the journal is not frequently cited by the community.

 

[Dale]

So it seems obvious that someone should analyze your proposed experiment using QFT to see what it predicts.

Yes.

@Pelion at this point we have discussed your paper here as far as we can given that the scientific community needs time to review and respond through the peer reviewed literature. In particular the community needs to evaluate the proposed experiment in terms of QFT and decide whether it makes any sense to base conclusions about FTL signaling using a theory which is known to be only valid for non relativistic speeds. (I have personal doubts that the community will accept such reasoning)

We will close the discussion of this paper at this point.