> On 5 Oct 2019, at 13:05, Bruce Kellett <[email protected]> wrote: > > On Sat, Oct 5, 2019 at 7:15 PM Bruno Marchal <[email protected] > <mailto:[email protected]>> wrote: > On 5 Oct 2019, at 07:14, Bruce Kellett <[email protected] > <mailto:[email protected]>> wrote: >> >> On Sat, Oct 5, 2019 at 1:10 AM Bruno Marchal <[email protected] >> <mailto:[email protected]>> wrote: >> On 3 Oct 2019, at 13:31, Bruce Kellett <[email protected] >> <mailto:[email protected]>> wrote: >>> And there is no FTL action -- that would be a local hidden variable causal >>> explanation, and Bell rules that out. >> >> This I do not understand, unless you bring t’Hooft super-determinism. In a >> unique universe, the violation of BI requires that when Alice do a >> measurement she influences and change the “map of the accessible reality” of >> Bob. They still cannot do signalling, but, with or without hidden variables, >> Alice does restrict instantaneously the state available Bob. Withe MW, as >> long as the light has not entangle Bob, Bob can make a measurement >> entangling him so other Alice of the multiverse. Everyone will agree with >> what the singlet state predicts, and no FTL signalling, nor influence has to >> occur. >> >> You contradict yourself, Bruno. You say "when Alice do a measurement she >> influences and changes the 'map of accessible reality' of Bob”. > > Yes, of course, but that influence propagate at a speed slower than light, > but successive entanglement “contagion”. > >> Then you say "Everyone will agree...no influence has to occur.” > > You confuse the Bobs to whom Alice can access, to the all Bobs, including > those Alice will never been able to access. > > Your twisting does not get you out of the fact that you have contradicted > yourself.
You need to be more specific than that. I don’t see the contradiction. I contradict only you interpretation of the wave, I think. > >> I think your complete failure to understand the non-local entangled state > > (Semantic play) > > You agreed that you did not understand the non-local entangled state. The only thing that I do not understand here is the non-locality of the entangled state in the One-universe interpretation of QM. > >> -- the fact that the wave function itself is non-local -- is at the root of >> all your misunderstandings, and leads you into these contradictory positions. > > No, you are not understanding what I said. Reread the post and the full > explanation. > > There is no full explanation in any previous post of yours. OK. One I have more time, I will re-explain more fully. > >> Let us start again. Consider the entangled singlet state that we have been >> talking about: >>> |psi> = (|+>|-> - |->|+>)/sqrt(2). >> This refers to two spacetime locations; > > You can’t at the start impose your own interpretation. You know that I > disagree with this interpretation since the start. > > For goodness sake, Bruno, what are you talking about? You cannot 'disagree > with this interpretation'. That is what the singlet state when the particles > have separated means. Meaning = interpretation. There is no consensus how to interpret the wave, even among “many-worlders”. Nothing is obvious here. > > > The singlet state refer to a continuum of relative worlds accessible to all > Alice and Bobs sharing the entangled particles. > > Ah, yes. Here we go again. Your really are confused by this state, Bruno. I take patronising remark like this one as a failure of your part. I just let you know. > You keep referring to the fact that it is rotationally invariant, and can be > analysed in any basis, as though that made a substantive difference. The > results obtain in any basis, true. But that is a trivial observation of > symmetry. It does not explain the observed experimental results. It explains it, without introducing any FTL action. > > >> let us call them (t1,x1) and (t2,x2), where the x1 and x2 stand for >> 3-vectors. The spacetime interval between these particles or events when >> measured, is s^2 = (t1-t2)^2 - (x1-x2)^2. When s^2 > 0, the separation is >> time-like, and when s^2 < 0, the separation is space-like (in the (+,-,-,-) >> metric that I am using. When Alice makes her measurement, she gets, say, >> 'up’. > > Now, all Alice get some result, some get ‘down' to. > > Read on, old son. You might find that this is mentioned below. > >> According to the above non-separable wave function, that means that Bob gets >> only the ket |->, > > That is vague. It means that Alice will access to the Bobs who get that > state, and never access to the Bobs who did not got it. > > Exactly. And this is what you are required to explain. Just stating it as a > fact is not an explanation. When Alice and Bob are separated, and measure their particles state, the MWI only ask that whatever they found will be correlated. In the world where Alice finds “up", Bob will find "down", and in the world where Alice finds “down”Bob will find “up”. But without any FTL action at a distance. > >> in the basis of Alice's measurement. Similarly if Alice gets 'down', Bob >> must measure the |+> ket, in Alice's basis. By rotating these kets into his >> local measurement basis, Bob gets 'up' or 'down' with the required >> probabilities. > … relatively to their corresponding Alices, only. > > Oh dear…… Yet, your problem seems that you evacuate those relative state, which enforces some real FTL influence from Alice to Bob. > >> This is a what your statement "when Alice do a measurement she influences >> and changes the 'map of accessible reality' of Bob" means. And I agree with >> this. > > I am not sure, because that influence never get higher than the speed of > light. > > Who said that it did? Read on and stop interrupting. Non-locality + one world assumption entails this, or refute any realist interpretation of the superposition, which are needed just to explain the two slits. > > > Bob could find a non correlated state, and that will mean that such Bob and > Alice are in different worlds, and will never meet. The state just describes > their possible relative states. > > The state describes the observed results. There are no "other worlds" in > which there are no correlated results. ? The state described the possible results of all possible measurement. Without collapse, the superpositions remain. > > >> So (this all assumes, without loss of generality, a frame in which Alice's >> measurement is first) Alice's measurement does inevitably affect the state >> that Bob can measure. > > Which Bob? She does not affect Bob’s state “physically”, she just learn that > she is in a universe in which she can access only to the Bob who will find > the correlated state, and never access to the Bob who get different states. > No FTL influence. > > No, no FTL influence. Read on. You haven't said anything of value yet. Aspect took a long amount of work to ensure that light has not the time to bring the correlation, and as the choice of “Alice”’s direction of spin measurement is arbitrary, unless you bring t’Hooft super determinism, the influence has to be FTL. Not so in the MWI. > > > If there is only one Alice and Bob, then there would be FTL influences. > > No. You can't get away from this idea, can you. Try and clear your mind of > its prejudices and think what non-local might mean. I am attempting to > explain it to you in words of one syllable. > >> The question then is, how does this effect come about? What is the >> mechanism? You appear to be only able to think of some FTL influence. > > No. You are the one inking this. > > You really are the limit, Bruno. You ascribe your own short-sightedness to > everyone else. Clear your mind of these prejudices, Bruno, and listen to what > I am saying. Patronising comment does not make your explanation more clear. > > > With the MW, at no moment Alice change the state of Bob. She just change her > own map of histories available. She knows that she can no more met a Bob with > another state than the correlated one. > > How does she know this? What is the magic? No magic. It is what the singlet state describe in the MW picture. > > That is why I take Aspect experience as an evidence of the other worlds, as I > do not give any sense to any FTL influence. > >> But that cannot work. There are a lot of problems with such an idea. Apart >> from violations of special relativity, it would involve the exchange of some >> particle or tachyon that conveys Alice's result and polarizer orientation to >> Bob *before* he makes his measurement. Dynamics for that might be >> conceivable, but there is a problem in deciding whether it is a particle or >> an FTL tachyon that must be exchanged. Notice that when this information has >> to be sent out from Alice's measurement, Bob still has not made his >> measurement, and there is no way at the spacetime point (t1,x1) to know when >> Bob will make his measurement. It could be at either space-like or time-like >> separation, s^2 > 0 or s^2 < 0, and there is no way of knowing, so there can >> be no suitable dynamics that will send a particle or a tachyon appropriate >> to the situation (because the situation is unknown at the relevant time). > > I agree. No FTL, but if the collapse exist and is a physical phenomenon, that > violation of Bell’s inequality make non-locality into FTL influence. That is > why I reject the uniqueness of Bob and Alice. > > The uniqueness or otherwise of Bob and Alice makes no difference. By > multiplying them you have not actually achieved anything. On the contrary. I get an explanation of the *appearance* of FTL non locality without any magic FTL. That is why the non-collapse interpretation is often used in quantum cosmology. > >> There is an additional dynamical problem in understanding how this particle >> or tachyon conveying Alice's information is actually going to affect Bob's >> state when it arrives there. If the correct statistics are to come out at >> the end, it would seem that this intermediate particle must suppress that >> part of Bob's state that is inconsistent with Alice's result. I leave the >> design of such dynamics to you -- it is beyond me to even begin to imagine >> it. On top of this, there is the problem that in some other frame, Bob's >> measurement is first, so his measurement must affect the joint state in a >> symmetrical way!!!!! >> >> I think this goes beyond impossibility to the point of absurdity. > That is my point, exactly. > > I am glad we can agree that FTL exchanges are out of the question. OK. But now, in one world interpretation of the singlet state, I don’t see how you can avoid FTL influence. > >> So what are we left with? I think we can rule out FTL interaction, or even >> sub-light speed interactions for time-like separations, because there are >> too many contradictory requirements on such a particle exchange of >> information. But the influence must occur, because the final correlations >> can only be explained in that way. (Attempts to explain the correlations >> away by MWI, or further interactions when the light cones overlap, have all >> failed. > Nope. You have not shown this. > > Well, I have looked at your "explanations", and at a lot of other MWI > so-called explanations, and not one of them has been satisfactory. These > "explanations" are either hopelessly vague, or they misunderstand what is > required, or, like Wallace, they simply wimp out of any explanation at all. > If you can do better, then do it. But despite years of asking, you still have > not come up with any credible explanation. It is the same as the one in Price FAQ, or in Tipler’s paper, and it is coherent with Deutsch-Hayden one, if recatsed in a many histories approach. Already in 1927, at Brussels’ Solvay congress, Einstein made clear, before EPR, that a physical collapse requires FTL influences. If the wave does not collapse “instantaneously”, the probability is non null that one particle leads to two dots on a screen. > >> Mainly because there are no relevant interactions at the point of overlap of >> the future light cones from the separated measurements.) >> >> We are left with a non-local influence, or interaction. Where by non-local, >> I mean precisely that -- an action on two separated spacetime points >> *without* there being any local causal contact between them, by exchange of >> particles or tachyons or whatever. If there were such an exchange, >> impossible as it seems, that would be a *local* explanation, because >> interactions via particle exchanges are the paradigm of locality. >> >> I know that this is contrary to all our instincts -- we believe that there >> is no "spooky action at a distance". And I know that your rejection of such >> action at a distance is why you have always called references to 'non-local' >> effects, FTL exchanges. > > I say explicitly the contrary!!!!!! > > Let's at least be honest about this, Bruno. You are always calling > non-locality, FTL action. That is not true. I say only that non-locality entails FTL in the One world picture. That is why I interpret Aspect experience as a confirmation of the many-histories/worlds/states. > > > I reject FTL, and do no need them, thanks to the MWI. You should reread > cautiously my post, as you attribute me the very idea that I reject. > > I am not ascribing belief in FTL action to you. Again, I ask you not to > misrepresent what I say. But you have not shown that MWI removes non-locality. It does not. It only change the interception of the BI in such a way that this non-locality (which I prefer to call inseparability) do no more implied FTL influence. Let us be clear on this: - non-locality = violation of BI (OK?) Then what I say is that in the MW picture, this does not imply FTL. But in a one world picture, where Bob and Alice are well defined and unique, that violation requires Alice measurement influencing Bob results, despite space-separated. > > >> I hope it is clear that I absolutely reject that interpretation, and do not >> think that any dynamical theory of such FTL exchanges could ever be made to >> work. >> >> Non-locality is exactly what it says -- a non-local influence or interaction >> between two points separated in space and time, whether by a space-like or a >> time-like interval -- call it "spooky action at a distance" if you must. But >> there is nothing spooky about it --no other rational explanation of the >> situation is available. > > So, you are the one introducing the spooky action, and indeed, if there is > only one couple Alice-Boob, that is the only solution, but with the MWI, we > don’t need them at all, as I have explained, but seems to have misunderstood > my post. > > I have read all your posts carefully, and have not misunderstood anything. > The trouble is that you have never explained how MWI removes non-local > influence. That lakes me doubt that you have read my post carefully. I did exactly that. I might try again when I have more time. > You always defer to some magical "matching of worlds" or some such. That is > not an explanation. I don’t see what “matching of worlds” refers in my explanation. > > >> Your further point about an infinity of different possible 'worlds' for >> Alice and Bob coming from the rotational invariance of the singlet state is >> just a smoke screen, having nothing to do with any rational explanation of >> what is going on. > > … that confirms you have fail to understand my point, as this is crucial in > exposing why the violation of BI implies only the necessity of many worlds or > many histories to avoid FTL influence. > > OK. I have failed to understand. Maybe that is because you have failed to > explain how this works. OK. I will try again. Actually I predicted indeterminacy, non-locality and non-cling of matter from just arithmetic + mechanism. So I am perhaps biased, as the MW seems to confirms those prediction. Mechanism is local by construction, yet the machines does discover that their local, accessible, reality is non local until they get the idea that their reality is a sum of all computations going through their state. Eventually tether is no world at all, only sigma_1 number relations (partial computable relations). > > > Please reread my explanation in my previous post, as it seems to me that you > have missed it. > > It is beginning to sound like this magical post in the past that John Clark > keeps referring to -- the post where you actually explain everything. The > trouble is that we cannot find any such post. “Explain everything?”. I never wrote such a post, but my papers explains my contribution in the field, if that is what you allude too. I guess the everything means the UDA and the translation of the UDA in arithmetic. You can read my sane04 paper, or my last papers on this for more: Marchal B. The computationalist reformulation of the mind-body problem. Prog Biophys Mol Biol; 2013 Sep;113(1):127-40 https://www.ncbi.nlm.nih.gov/pubmed/23567157 Marchal B. The Universal Numbers. From Biology to Physics, Progress in Biophysics and Molecular Biology, 2015, Vol. 119, Issue 3, 368-381. https://www.ncbi.nlm.nih.gov/pubmed/26140993 B. Marchal. The Origin of Physical Laws and Sensations. In 4th International System Administration and Network Engineering Conference, SANE 2004, Amsterdam, 2004. http://iridia.ulb.ac.be/~marchal/publications/SANE2004MARCHALAbstract.html (sane04) > > Bruce > > -- > 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 [email protected] > <mailto:[email protected]>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/everything-list/CAFxXSLTOD%2BKYbNfJ8eMsSf5HkCpbv5BBpvsdn8Y6n8JCo%3DvsFw%40mail.gmail.com > > <https://groups.google.com/d/msgid/everything-list/CAFxXSLTOD%2BKYbNfJ8eMsSf5HkCpbv5BBpvsdn8Y6n8JCo%3DvsFw%40mail.gmail.com?utm_medium=email&utm_source=footer>. -- 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/60298089-93BD-457E-9DB1-06BCBAE78ABE%40ulb.ac.be.
