Local realism ruled out? (was: Photon entanglement and...)by akhmeteli Tags: entanglement, local, photon, realism, ruled 

#793
Oct3112, 05:13 AM

P: 3,178

As a reminder: 



#794
Jan1413, 07:22 AM

P: 582

I am writing this without any Schadenfreude. I do appreciate that a loopholefree experiment can be performed any moment now. It looks like the race to conduct the first experiment of this kind is really fierce. E.g., the following quote is interesting (SCIENCE, VOL 331, P. 1380 (2011)): “Zukowski thinks the race to close all the loopholes simultaneously will soon be over. “Conservatively, it could take another 5 years to complete, but it could also be done tomorrow,” he says. “We’re at the stage where everyone is scared to read their competitors’ papers, in case they find they have been beaten. The only real question is: Who will win?”” I also had this impression of a fierce race listening to talks on quantum foundations experiments at several conferences last year. On the other hand, some experimentalists admitted (typically, not in their official talks:) ) that they encounter some formidable challenges. So I am just trying to say that these three years since the start of this thread have demonstrated again that it is extremely difficult to demonstrate violations of the genuine Bell inequalities. Will they be demonstrated by the fiftieth anniversary of the Bell’s article next year? Or ever? My prediction is “no”. But I may be mistaken. 



#795
Jan1413, 02:02 PM

P: 141





#796
Jan1413, 08:53 PM

P: 582

I tried to explain in my post 753 in this thread why I cannot agree with you. 



#797
Jan1513, 12:46 AM

P: 582

Another thing: "the foundations of quantum mechanics ... remain hotly debated in the scientific community, and no consensus on essential questions has been reached." (Schlosshauer, Kofler, Zeilinger, http://arxiv.org/abs/1301.1069 ). So disagreement is a "new normal" for quantum foundations. 



#798
Jan1513, 12:14 PM

P: 79





#799
Jan1513, 08:19 PM

P: 582





#800
Jan1613, 04:56 AM

P: 3,178





#801
Jan1613, 01:55 PM

P: 79





#802
Jan1613, 09:23 PM

P: 582





#803
Jan1613, 09:57 PM

P: 79

The incompatibility between qm and lhv has been mathematically proven. They necessarily predict a different correlation between θ and rate of coincidental detection. So, if qm is correct, then (Bell) lhv models of quantum entanglement are ruled out. I'm betting that qm will continue to be confirmed, even in a loopholefree test. 



#804
Jan1613, 10:54 PM

P: 582





#805
Jan1613, 11:49 PM

P: 582

Realism, in my book, is not the realism of the EPR article, i.e. I don't believe that, say, a particle has definite values of coordinates, momentum, spin projections, etc., whether the relevant observables are measured or not. You may say that I do not seek noncontextual hidden variables. The version of realism that I accept is contextual: any state can be described by some set of parameters that uniquely define the state's evolution. I would not call those parameters "hidden variables", as, say, in the models of my articles, they are not exactly hidden: they are the potentials of the electromagnetic fields and their derivatives. This version is "contextual" as the set of parameters must describe the relevant instruments as well. 



#806
Jan1713, 12:22 AM

P: 79

What do you think is the likelihood of a loopholefree test in the foreseeable future? 



#807
Jan1713, 02:38 AM

P: 3,178





#808
Jan1713, 08:59 PM

P: 582





#809
Jan1713, 10:33 PM

P: 79





#810
Jan1813, 05:28 AM

P: 582




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