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Why are Bell's inequalities violated? 
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#73
Jan2613, 07:23 PM

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At first glance, this might appear to be a limitation of Bell's model, but in fact these models do cover just about anything that an intuitive layman (and probably Einstein, Podolosky, Rosen and kindred spirits) would accept as "nonweird". Thus, the real importance of Bell's inequality and its observed violations is that we're stuck with quantum weirdness. PostBell, we don't talk about whether the world is weird, we talk about how to deal with that weirdness. 


#74
Jan2613, 08:20 PM

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#75
Jan2613, 08:35 PM

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http://www.futuretg.com/FTHumanEvolu...0Mechanics.pdf 


#76
Jan2613, 09:08 PM

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Its been close to 50 years and why Bells inequalities are violated has not been explained.
So first , is it possible to have ' spin rotations ' and ' geometric phase' as taken from the PDF paper I referenced ? If not then Admin can delete this post. But if so then A(aλ)=±1 where λ is a phase variable related to entangled two photon spins from a Calcium atoms' 6_{s} level can be considered. And this table: A________B xyz______xyz +++______ ++______+ ++______+ +______++ ++______+ +______++ +______++ ______+++ And this P[xz+]≤ P[y+x] + [x+z+] being violated could be explained by the above table not having fixed values but with ' rotating spins ' and it would be like an 8 level slot machine set in motion. The challenge would be to explain why the spins at two equal angular settings are always opposite. Im only taking the initiative here because the question is not being answered when limited to EPR/Bell realism 


#77
Jan2713, 12:22 AM

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BIs are based on a linear correlation between θ and rate of coincidental detection, which is due to the form that Bell's locality condition requires his lhvsupplemented qm expectation value formulation to take, ie., that the probability distribution be factorizable into the functions that determine individual detection. I mentioned in an earlier post that A(a,λ)=±1, B(b,λ)=±1 are Bell realism. A(a,λ) and B(b,λ) are also explicitly local. As opposed to the explicitly nonlocal A(a,b,λ) and B(a,b,λ), A(a,λ) and B(b,λ) specify that A doesn't depend on b, and B doesn't depend on a. The intensity of light (or photon flux) transmitted by the analyzing (or second) polarizer in sequenced two polarizer (local) setups is always a nonlnear function of the angular difference of the polarizer settings. (In the two polarizer Bell test setups both polarizers are the analyzer, and rate of coincidental detection is intensity.) BIs are (must be) violated because a necessarily linear correlation expectation is being applied to a setup that must necessarily (even if nothing nonlocal is happening, as in local sequenced setups) produce nonlinear correlations. 


#78
Jan2713, 04:42 AM

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#79
Jan2713, 10:46 AM

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I don't quite understand your question. Because Bell's equation follows from Hidden variable and statistics which is orthogonal to QM prediction.
And it is later EXPERIMENTALLY proven to be violated. Maybe the only thing we could ask is the validity of the experiment rather than the reason... Personal opinion 


#80
Jan2713, 07:22 PM

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#81
Feb313, 01:23 PM

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#82
Feb313, 03:08 PM

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#83
Feb313, 04:50 PM

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#84
Feb413, 10:04 AM

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I call anything nonrealistic if the interpretation has as adjunct that there are no values for counterfactual measurements  i.e. there is a dependency on the observer. I call anything local if there exists a light cone bounded by c which limits propagation of effects. So by that, TS is local nonrealistic. MWI is the same. And to me, Bohmian class theories are nonlocal AND nonrealistic (because there is always a measurement context to consider). By contrast: I have seen Relational Blockworld (a TS class theory) described by one of its authors as both local and realistic. MWI is often called local realistic. And Bohmian is often described as nonlocal realistic. Yet by the definitions of EPR, I think my viewpoint is just fine. I don't think it matters all that much, the essential points seem to come out the same in the end. 


#85
Feb713, 03:20 PM

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Superluminal causation: One option for explaining Bell correlations causally is to assume that there are some superluminal causes, for instance, a causal influence from the outcome on one wing to the outcome on the other, or from the setting on one wing to the outcome on the other, or both. In the most general case one allows hidden variables that can causally influence the measurement outcomes. Retrocausation: "Retrocausation" refers to the possibility of causal influences that act in a direction contrary to the standard arrow of time. It has been proposed as a means of resolving the mystery of Bellinequality violations by purportedly saving the relativistic structure of the theory: rather than having causal influences propagating outside the light cone, they propagate within the light cone although possibly within the backward light cone. The authors also discuss some of the difficulties in distinguishing retrocausality from superluminal causation: http://arxiv.org/pdf/1208.4119v1.pdf To be honest, I've always found Gisin's description as quantum correlations lying *beyond* spacetime as the most interesting suggestion. At first it didn't make sense to me but then, when one thinks about the early "creation" of matter and space, it seems that it appeared out of something prespatial/temporal. So, why can't a remnant of that "prespatial stuff" still be with us at some level and play some role in physical laws. I understand this is mere speculation. But others have suggested this: http://spot.colorado.edu/~monton/Bra.../Articles.html 


#86
Feb1713, 11:56 PM

P: 373

Its a fact that the Bells inequalities are violated for expected spin measurements when detector settings are not parallel. And its natural to consider: loopholes . Clifford algebra, disproofs.superluminal signals. time reversal, many worlds, no conspiracy, and other theories to explain the experimental results that do not agree with local realism.A local realism that assigns ± spin values based on perfect correlations when detector settings are parallel. It seems there is alot of talent here and out there devoting time to the above theories to the exclusion of exactly what the mechanism is that is causing the violations. When the research focus should be on why and how spins of entangled particles change.



#87
Feb1813, 02:24 AM

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#88
Feb1813, 10:48 AM

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This very succinctly defines something I suspected about your perspective from previous debates, and indicates a lot of disagreement is mere semantics. I even considered a thread asking for how people defined nonrealism in this context. Has it occurred to you that Relativity is a nonrealistic theory under this definition? In fact you can use an ad hoc characterization of the addition of velocities equation to violate Bell's inequality, even slightly more so than EPR correlations do. To illustrate consider the composition law for velocities. If we try to call a velocity 'real' in the EPR sense it is easy to demonstrate that the counterfactual velocities do not add up. For instance consider 2 spaceships A and B leaving a point of origin at 50% c. This entails that A and B have a velocity of 80% c relative to each other. If you boost the point of origin toward A then A will lose relative velocity faster than B gains relative velocity. In effect there is no counterfactual total value for composite velocities. All thermodynamic state variables as well as velocity, momentum, energy, entropy, etc., associated with a classical object can be demonstrated to have the same lack of counterfactual properties. From this you can create an ad hoc analogy with EPR correlations, which can be made to violate Bell's inequality even more than EPR correlations. Just assign a probability for a gun at the point of origin to destroy the spaceships in proportion to the relative velocity, or total momentum. You can also treat the ships as doppelgangers such that if a given speed destroys A that same speed destroys B, or other variations. The key feature is that velocities lack a counterfactual total value. A destroyed ship is then analogous to an EPR path A, and survival is path B. The survival correlations between spaceship A and B will then not counterfactually add up under different boost of the gun. If this is the nature of the variables you define as nonrealistic then I would go so far as to bet that all variable we have direct empirical access to are nonrealistic, that the world we perceive as physical is actually a purely relational construct. Once you recognize the classical absurdity of parts with a background of absolute space and time, where space and time are preexisting independent variables as if by magic, this notion of realism is prima facie absurd. Once you accept these variables we call space and time, as we measure them, as state variables then the loss of counterfactual variables, even for a basic variable like velocity or photon paths in EPR, is assured. Classically we had masses or particles to underpin the relational variables lacking counterfactuals, which we replaced with 'proper' values requiring an observer frame. It is the nature of these particles we are now dealing with. The real difference in the perspective of a realist, at least a serious one, is not the loss of counterfactuals, but a lack of underpinning real variables to generate them. Yet the problem is we know that we can't use a backdrop of space and time to put them in, since these variables are required to be the generators of space and time itself. Bottom line is that given you definition of nonrealism a serious realist can't honestly object. What realist seek is a substructure model that provides what particles provided for classical physic. We can't return to Newtonian style realism but we already know how wrong this is even without resorting to QM. I don't think you have addressed the issues of interest to realist. 


#89
Feb1813, 05:45 PM

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Inasmuch as most inflationary cosmogenies seem to entail some sort of 'quantum fluctuation' originating at a nanoscopic scale, why should we assume that its quantum attributes were necessarily entrained in the expansion of 4space, or dependent on the evolution of the forces? Since the evidence shows nonlocality only too clearly and no forcemediation involvement whatever, isn't it simpler, more elegant, and more Einsteinianly beautiful to assert locality (I find realism 'meh, take it or leave it'—I have no preference) to be an extraordinary claim requiring extraordinary evidence? Edit: or to use a biological analogy: all living systems, however much evolved, retain something of the original RNAworld. 


#90
Feb1813, 09:35 PM

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http://www.nyu.edu/gsas/dept/philo/c...nessSpace.html 


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