Double-slit experiment with photons vs electrons

[bohm2]

While his thoughts on Bell might be elegant, he still has the problem that he proposes a classical-field-like model and has to explain somehow why we see evidence for single photon states in antibunching experiments. Here, he can only blame the detectors and claim that the physics of detectors is not properly understood and more "ideal" detectors will help clarify. However, this is also the point most people do not buy. See also the above manuscript by the Weihs group (which may or may not have been directly motivated by ideas similar to Khrennikov's) on the validity of the Born rule in terms of higher-order effects.

I haven't read his paper yet, but he has published a paper arguing that bunching and anti-bunching for quantum systems can be represented in the classical signal framework. I'm not sure if his model is motivated by the above group but these authors were not referenced in his paper. I wish I had a stronger mathematical background because I have trouble making sense of these arguments but I do know that Khrennikov is a major player in the Emergent QM group that have had 2 previous conferences: See http://www.emqm13.org/ and http://www.univie.ac.at/hvf11/congress/EmerQuM.html

Classical signal viewpoint to bunching and anti-bunching
http://arxiv.org/pdf/1105.4268.pdf

 

[TrickyDicky]

But people already checked for violations of Born's rule and the presence of higher-order terms. See "Ruling Out Multi-Order Interference in Quantum Mechanics", Science 23 July 2010: Vol. 329 no. 5990 pp. 418-421 or check the ArXiv version here: http://arxiv.org/abs/1007.4193. They have not found any deviations.

Sure, I would not expect to see any deviation within their experimental limits, if it exists it is too small to be detected at the bound they use and certainly not unless the interference is tested on big enough molecules as they say in their closing lines.
We know that in the classical macroscopic world (i.e. in water waves)we observe nonlinear interference from highly nonlinear waves, it is to be expected that if there is any nonlinearity at the microscopic scale it has a very small effect.

 

[Cthugha]

Yes, at least much of the time. When designing equipment that is used for single photon experiments you can always(?) use Maxwell's equations for the design process.

To add to ehat has been said: From my experience you are ok using Maxwell's equation as long as you are interested in mean intensities and quantities related to them. As soon as you are interested in correlations (experiments using coincidence counting), Maxwell's equations will only work for coherent light.

I haven't read his paper yet, but he has published a paper arguing that bunching and anti-bunching for quantum systems can be represented in the classical signal framework.

That paper is not really about the problem at hand here. He shows that in his model boson-like entities show bunching and fermion-like entities show antibunching. This is well known and has been shown, e.g. for Helium 3 and Helium 4. It is more or less a consequence of sign changes when calculating probability amplitudes for events having these entities end up in the same state. His model reproduces these predictions. What he does not show is that his model can also show antibunching for boson-like entities under "blockade" conditions. For example a single atom will only emit a single photon at a time because one needs to reexcite it before it can emit again, so there is this blockade which makes a bosonic system behave like a fermionic one. The question of how to reproduce this effect using classical fields is the central one and in my opinion there is no classical field-like model doing that in a satisfying manner. Usually that is the point where those theories claim that common detector physics is wrong which is not convincing to me.

We know that in the classical macroscopic world (i.e. in water waves)we observe nonlinear interference from highly nonlinear waves, it is to be expected that if there is any nonlinearity at the microscopic scale it has a very small effect.

But it is pretty trivial that you get nonlinearities when going to media, no? Well, of course one can always go ahead and find a better bound in experiment.

 

[TrickyDicky]

But it is pretty trivial that you get nonlinearities when going to media, no?

Yes, it is implicit in my analogy that in the microscopic case the quantum vacuum may be considered a nontrivial nonlinear medium. This is theoretically expected as I commented previously above the Schwinger limit in QED, but I'm wondering if this kind of nonlinearity could be considered in principle also at low energies as a source of "wavefunction collapse behaviour". I'm taking this line of thought(just in case it rings some bell) from Nobel recipient Bob Laughlin ideas about the emergent quantum vacuum as a kind of phase of matter.

 

[San K]

Is it not just the double slit (or other interference experiments) but many other interactions?

where the equations used to model photon behavior are different from those used for electrons...