[tjradcliffe]

This paper has a variety of issues, the most glaring of which is that their "explanation" of the experimental violation of Bell's inequalities (specifically the CHSH form that has been realized in many experiments on polarization) is dependent on a static setup of precisely the kind that Aspect's experiments were intended to avoid.

Aspect's work is one of the most beautiful pieces of careful and precise experimental testing of an idea in the past half-century, and while it has been attacked from many perspectives it is still a very robust argument for the non-locality of reality. One of the important things about it is that the polarization direction was switched in a quasi-random way after the photons had left the source. Variations on this trick have been performed since, and they all agree with the predictions of quantum theory.

The authors say in this paper "The CHSH assumption is not true in Faraday's model. Instead there is prior communication of orientation along phase vortices such as(4), communication which the CHSH calculation excludes by its explicit assumption."

In experiments like Aspects, prior communication is ruled out because the experimental setup is varied in one arm of the apparatus outside forward light cone of the other photon. Each photon gets detected before the other one could possibly know (based on signalling at the speed of light) what polarizer orientation it should be lined up with.

So this is an interesting bit of work that might be useful in creating photonic quasi-particles in magnetic fluids that would allow for study of photon properties that might be difficult to get an experimental handle on otherwise, but the claim that they have a classical model that violates Bell's inequalities in a way that is relevant to the actual experimental work done in this area is considerably overblown.

[GregBuchholz]

I'm not a physicist, but I've always wondered about Caroline Thompson's work, like:

"Chaotic Ball" model, local realism and the Bell test loopholes

http://arxiv.org/abs/quant-ph/0210150

...any thoughts?

[tjradcliffe]

The scrutiny that Bell test experiments get from loophole people is always much appreciated, but the problem with Aspect's results in particular is that lovely parenthetical remark that appears in several of his figures, to the tune of "The dotted line is not a fit to the data, but the quantum mechanical prediction for this result."

While it is easy to imagine selective-detection effects that mess up the results enough to invalidate the test at the level of the inequality, it is very, very difficult to maintain all the physics required for precise, detailed agreement between theory and experiment of the kind that Aspect and others have shown. Here is an example of a "local realistic model" that reproduces the quantum mechanical results for in-time coincidences, but completely messes up any number of auxiliary measurements: http://www.tjradcliffe.com/?p=590

So while I'd love to see a modern version of Aspect's work using state-of-the-art entangled photon sources and the like, the likely reason it hasn't been done is that the odds of it revealing anything new and different are trivially small (but not zero, of course!)