R: Re: R: Re: R: Re: Non-locality and MWI (literature)
Following the above reasoning MWI (if it is a truly deterministic theory) should violate the locality condition. I doubt this, but if you find a proof, in the literature (or not), I am interested. As I explained, and also give references, it seems to me that the MWI restores both 3p determinacy and 3p locality, making both the indeterminacy and non-locality only first person plural phenomenological happening. That is also Everett's position, and I would say the position of most Everettian (I still don't find any Everettian claiming that the MWI remains non-local, except the beginners who often think at first that the entire universe split instantaneously, but this does not deserve to be commented as nobody believes in this anymore). Bruno Jarrett, but also Shimony, and also Ghirardi, gave the proof that a *deterministic* QM (I should say a *deterministic and single-valued* QM) must violate the Locality Condition. I do not have references at hand, right now. I'll write down something as soon as possible. I did not re-read it, but a paper (about differences between non-separability, non-locality, determinism, etc.) could be this one http://dropcanvas.com/#n9m72p90WEc54O (I hope the link works) -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
R: Re: R: Re: R: Re: Non-locality and MWI (literature)
Bruce: I came across the following brief statement by Goldstein et al: Many-worlds and relational interpretations of quantum theory [etc.] # Adrian Kent writes: "Making scientific sense of Everett’s idea is difficult, as evidenced by the many and generally incompatible attempts to show how unitary quantum theory explains the appearance of a quasiclassical world and the apparent validity of the Born rule and Copenhagen quantum theory, and evidenced also by the problems with all of these attempts. There is still nothing close to a consensus on the most promising way forward, even among many-worlds enthusiasts. This adds motivation for developing alternative ways of formulating quantum theory that have the purported advantages of many-worlds ideas — realism, and Lorentz invariance — but describe a single real world, so avoiding both the conceptual problems and the fantastic nature of many-worlds ideas. Still, for many, the appeal of many-worlds ideas evidently persists." in http://arxiv.org/abs/1408.1944 "Does it Make Sense to Speak of Self-Locating Uncertainty in the Universal Wave Function?" see also http://arxiv.org/abs/0905.0624 and http://arxiv.org/abs/gr-qc/9703089 -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
R: Re: R: Re: R: Re: R: Re: Non-locality and MWI (literature)
. I think we all agree that QM-with-collapse entails a violation of Locality. The debate was for the case of the non-single value QM, that is QM-without-collapse, where all branches of the wave are kept "alive". Bruno As somebody wrote "Algebraic nonseparability entails geometric nonlocality; emphasis on its time aspect can be worded atemporality." (Olivier Costa de Beauregard). And yes, in QM without collapse (without reduction of probability packet), all branches are kept alive (with some probability or weight attached to each world; with a conservation of energy not well defined in each world or, better, during each split; and with a strange concept of locality - because there are "many" decohering "worlds"). s. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
Re: R: Re: R: Re: R: Re: Non-locality and MWI (literature)
On 10 May 2016, at 19:06, 'scerir' via Everything List wrote: Messaggio originale Da: Bruno Marchal <marc...@ulb.ac.be> Data: 10/05/2016 18.31 A: <everything-list@googlegroups.com> Ogg: Re: R: Re: R: Re: Non-locality and MWI (literature) On 10 May 2016, at 15:37, 'scerir' via Everything List wrote: Thanks Scerir, but yet again, this paper get the same conclusion as mine (and most people here). With the MWI, non-locality does not imply action-at-a distance. (d'Espagnat would call it non- separability). What I look for would be a paper which would show that in the MWI there are action-at-a-distance, like Bruce and John C claim. I might comment later, as I am late in my scheduling, but will just notice that Gisin's paper (mentionned by Brent) use the non- compatibilist theory of free-will, which makes no-sense to a mechanist. I think Brent concluded similarly. Bruno If A and B are two wings of a typical Bell apparatus, i the observable to be measured in A and x its possible value, j is the observable to be measured in B and y its possible value, and if Lambda are hidden variables, we could write Locality Condition p_A,Lambda (x|i,j) = p_A,Lambda (x|i) p_B,Lambda (y|i,j) = p_B,Lambda (y|j) Separability Condition p_A,Lambda (x|i,j,y) = p_A,Lambda (x|i,j) p_B,Lambda (y|i,j,x) = P_B,Lambda (y|i,j) There is (was) some agreement that a (phantomatic) deterministic theory (i.e. one in which the range of any probability distribution of outcomes is the set: 0 or 1) ? The question is: are the probabilities, or the indeterminacies, and the non locality, phenomenological (1p) or factual (ontological, real, 3p)? QM+collapse admit factual indeterminacies (God plays dice, and there are action at a distance, even if they cannot be used to transmit signal quicker than light). QM-without-collapse is purely deterministic at the 3p level, and admits indeterminacies at the phenomenological level. I think everyone agree on this. The debate is on the following question: does QM-without-collapse admit factual non-locality (real physical action at a distance, like QM-with-collapse), or do the non-locality becomes, like the indeterminacy, phenomenological? (I think yes, as Jesse, Saibal and others, but it seems Bruce and John C. differ on this). Frankly it is not easy for me to say anything about that, at least something consistent. Mainly because "Many-worlds with its multiplicity of results in different worlds violates CFD, of course, and thus can be local. Thus many-worlds is the only local quantum theory in accord with the standard predictions of QM and, so far, with experiment.". reproducing all the predictions of QM, can not violate the Separability Condition, (the specification of Lambda, i, j, in principle determines completely the outcomes x, y, then any additional conditioning on x or y is superfluous, having x and y just one value allowed, so they cannot affect the probability, which - in a deterministic theory - can just take the values 0 or 1) and must violate the Locality Condition. Following the above reasoning MWI (if it is a truly deterministic theory) should violate the locality condition. I doubt this, but if you find a proof, in the literature (or not), I am interested. As I explained, and also give references, it seems to me that the MWI restores both 3p determinacy and 3p locality, making both the indeterminacy and non-locality only first person plural phenomenological happening. That is also Everett's position, and I would say the position of most Everettian (I still don't find any Everettian claiming that the MWI remains non-local, except the beginners who often think at first that the entire universe split instantaneously, but this does not deserve to be commented as nobody believes in this anymore). Bruno Jarrett, but also Shimony, and also Ghirardi, gave the proof that a *deterministic* QM (I should say a *deterministic and single- valued* QM) Yes, that is important to add. It was notoriously implicit in EPR and Bell 1964, even after. must violate the Locality Condition. EPR and Bell shows this, and the usual papers (Clauser and Horne, Clauser Horne Shimony, Holt, Aspect, ...). I do not have references at hand, right now. I'll write down something as soon as possible. I think we all agree that QM-with-collapse entails a violation of Locality. The debate was for the case of the non-single value QM, that is QM-without-collapse, where all branches of the wave are kept "alive". Bruno -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything- l...@go
R: Re: R: Re: R: Re: Non-locality and MWI (literature)
Messaggio originale Da: Bruno Marchal <marc...@ulb.ac.be> Data: 10/05/2016 18.31 A: <everything-list@googlegroups.com> Ogg: Re: R: Re: R: Re: Non-locality and MWI (literature) On 10 May 2016, at 15:37, 'scerir' via Everything List wrote: Thanks Scerir, but yet again, this paper get the same conclusion as mine (and most people here). With the MWI, non-locality does not imply action-at-a distance. (d'Espagnat would call it non-separability). What I look for would be a paper which would show that in the MWI there are action-at-a-distance, like Bruce and John C claim. I might comment later, as I am late in my scheduling, but will just notice that Gisin's paper (mentionned by Brent) use the non-compatibilist theory of free-will, which makes no-sense to a mechanist. I think Brent concluded similarly. Bruno If A and B are two wings of a typical Bell apparatus, i the observable to be measured in A and x its possible value, j is the observable to be measured in B and y its possible value, and if Lambda are hidden variables, we could write Locality Condition p_A,Lambda (x|i,j) = p_A,Lambda (x|i) p_B,Lambda (y|i,j) = p_B,Lambda (y|j) Separability Condition p_A,Lambda (x|i,j,y) = p_A,Lambda (x|i,j) p_B,Lambda (y|i,j,x) = P_B,Lambda (y|i,j) There is (was) some agreement that a (phantomatic) deterministic theory (i.e. one in which the range of any probability distribution of outcomes is the set: 0 or 1) ? The question is: are the probabilities, or the indeterminacies, and the non locality, phenomenological (1p) or factual (ontological, real, 3p)? QM+collapse admit factual indeterminacies (God plays dice, and there are action at a distance, even if they cannot be used to transmit signal quicker than light). QM-without-collapse is purely deterministic at the 3p level, and admits indeterminacies at the phenomenological level. I think everyone agree on this. The debate is on the following question: does QM-without-collapse admit factual non-locality (real physical action at a distance, like QM-with-collapse), or do the non-locality becomes, like the indeterminacy, phenomenological? (I think yes, as Jesse, Saibal and others, but it seems Bruce and John C. differ on this). Frankly it is not easy for me to say anything about that, at least something consistent. Mainly because "Many-worlds with its multiplicity of results in different worlds violates CFD, of course, and thus can be local. Thus many-worlds is the only local quantum theory in accord with the standard predictions of QM and, so far, with experiment.". reproducing all the predictions of QM, can not violate the Separability Condition, (the specification of Lambda, i, j, in principle determines completely the outcomes x, y, then any additional conditioning on x or y is superfluous, having x and y just one value allowed, so they cannot affect the probability, which - in a deterministic theory - can just take the values 0 or 1) and must violate the Locality Condition. Following the above reasoning MWI (if it is a truly deterministic theory) should violate the locality condition. I doubt this, but if you find a proof, in the literature (or not), I am interested. As I explained, and also give references, it seems to me that the MWI restores both 3p determinacy and 3p locality, making both the indeterminacy and non-locality only first person plural phenomenological happening. That is also Everett's position, and I would say the position of most Everettian (I still don't find any Everettian claiming that the MWI remains non-local, except the beginners who often think at first that the entire universe split instantaneously, but this does not deserve to be commented as nobody believes in this anymore). Bruno Jarrett, but also Shimony, and also Ghirardi, gave the proof that a *deterministic* QM (I should say a *deterministic and single-valued* QM) must violate the Locality Condition. I do not have references at hand, right now. I'll write down something as soon as possible. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout. http://iridia.ulb.ac.be/~marchal/ -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https:
