joigus Posted October 3, 2022 Posted October 3, 2022 (edited) 2 hours ago, bangstrom said: I could cite any number of authorities who find entanglement and non-locality as valid. This is the mainstream view since it has been established experimentally. The burden of proof is on the person, you, making the extraordinary position. I can name one more who might agree with Gell-Mann and Susskind and that is A.F. Kracklaurer. Can you name another? That’s a great idea for a new experiment. I can supply the tardigrades. If you pass a single particle through a single slit, it produces an interference pattern due to diffraction.If you pass a single particle through a double slit it produces a double slit interference. If you try again with 3,4 or 5 slits, you get increasingly complex interference patterns. How does a single particle passing through multiple slits ‘know’ how many slits are to its left or right so it can land in the proper position with the appropriate pattern? There must be something non-local going on. Experimentally it is possible to select a detector to make the first measurement. The timing is much like it is done at the track. This is serious physics. I suspect next year this will announced as a winner of the Ig Nobel prize. https://arxiv.org/abs/2112.07978 Entanglement between superconducting qubits and a tardigrade K. S. Lee, Y. P. Tan, L. H. Nguyen, R. P. Budoyo, K. H. Park, C. Hufnagel, Y. S. Yap, N. Møbjerg, V. Vedral, T. Paterek, R. Dumke Quantum and biological systems are seldom discussed together as they seemingly demand opposing conditions. Life is complex, "hot and wet" whereas quantum objects are small, cold and well controlled. Here, we overcome this barrier with a tardigrade -- a microscopic multicellular organism known to tolerate extreme physiochemical conditions via a latent state of life known as cryptobiosis. We observe coupling between the animal in cryptobiosis and a superconducting quantum bit and prepare a highly entangled state between this combined system and another qubit. The tardigrade itself is shown to be entangled with the remaining subsystems. The animal is then observed to return to its active form after 420 hours at sub 10 mK temperatures and pressure of 6×10−6 mbar, setting a new record for the conditions that a complex form of life can survive. This is not peer-reviewed work. Cornell's repository is for preprints, not papers. I don't see the peer-reviewed paper anywhere. What I have found is a bunch of people saying this is nonsense: https://phys.org/news/2021-12-peers-dispute-tardigrades-entangled-qubits.html And I agree. I'll keep an eye on it just in case. Quote This is serious physics. I suspect next year this will announced as a winner of the Ig Nobel prize. Don't hold your breath. I see you have no idea how long it takes for a "groundbreaking" paper to get approved for publication, and once there, how long it takes for a Nobel prize to be awarded. You've watched too much Big Bang Theory. Give it a rest. And study some quantum mechanics in the meantime. Quote One thing that most did agree on was that the researchers had found a new level of robustness for tardigrades—some of those in the experiments had survived extremely inhospitable conditions near absolute zero and pressures as low as 0.000006 millibars for up to 17 days, and then revived and resumed their regular existence after conditions were returned to normal. Edited October 3, 2022 by joigus text formatting
joigus Posted October 3, 2022 Posted October 3, 2022 Quote Most of those commenting on the research noted that the coupling observed by the researchers could have been observed with or without entanglement. They also noted that placing a tardigrade on top of a qubit could result in altering the frequency of the qubit, but that is not the same thing as the two being entangled. Also, the tardigrade was not able to act as a single quantum object. In short, they suggest that the claim of entangling a tardigrade with a pair of qubits was completely false.
bangstrom Posted October 3, 2022 Posted October 3, 2022 1 hour ago, joigus said: Don't hold your breath. I see you have no idea how long it takes for a "groundbreaking" paper to get approved for publication, and once there, how long it takes for a Nobel prize to be awarded. When the work is really "ground breaking", Iggy Nobel wastes no time to pick a winner. The tardigrade experiment is an Ig Nobel prize winner for sure.
joigus Posted October 3, 2022 Posted October 3, 2022 41 minutes ago, bangstrom said: When the work is really "ground breaking", Iggy Nobel wastes no time to pick a winner. The tardigrade experiment is an Ig Nobel prize winner for sure. Oh, an Iggy. LOL. Sure, as a joke it's really good. The claims of what it implies is what I find more "ignoble."
Eise Posted October 3, 2022 Posted October 3, 2022 (edited) 5 hours ago, bangstrom said: I can name one more who might agree with Gell-Mann and Susskind and that is A.F. Kracklaurer. No, you turn it around: instead of providing references of QM specialists who see 'real superluminal connections', you provide a link to a physicist who denies none-locality, strengthening my position. Try again. 5 hours ago, bangstrom said: If you pass a single particle through a single slit, it produces an interference pattern due to diffraction.If you pass a single particle through a double slit it produces a double slit interference. If you try again with 3,4 or 5 slits, you get increasingly complex interference patterns. Yes, you are completely right. I would suggest that you read Feynman's QED: The Strange Theory of Light and Matter. Then you can wonder why the principle of least action seems to work in classical physics (Lagrange formulation of classical physics, Fermat's theorem etc), in relativity, and in QM (QED). E.g. taking Fermat's theorem, how does the light in advance know what is the fastest way between two points? Must be non-locality... . 16 hours ago, Eise said: Not with tardigrades. But if you have a source, let us know. OK, this was already reacted on by Joigus. However, @joigus, I think you make an error in your argumentation. Interference experiments with buckyballs have succeeded. Quote Quantum superposition lies at the heart of quantum mechanics and gives rise to many of its paradoxes. Superposition of de Broglie matter waves has been observed for massive particles such as electrons, atoms and dimers, small van der Waals clusters, and neutrons. But matter wave interferometry with larger objects has remained experimentally challenging, despite the development of powerful atom interferometric techniques for experiments in fundamental quantum mechanics, metrology and lithography. Here we report the observation of de Broglie wave interference of C60 molecules by diffraction at a material absorption grating. This molecule is the most massive and complex object in which wave behaviour has been observed. Of particular interest is the fact that C60 is almost a classical body, because of its many excited internal degrees of freedom and their possible couplings to the environment. Such couplings are essential for the appearance of decoherence, suggesting that interference experiments with large molecules should facilitate detailed studies of this process. But if I follow your argumentation regarding the tardigrades, and apply this to buckyballs, that would have been: 60 x 6 = 360 electrons 60 x 1 = 60 nuclei makes 420 particles Or should I go further, and count the nucleons? 60 x 6 = 360 electrons 60 x 12 = 720 nucleons makes a total of 1080 particles. I simply think, that because the nucleus is a bound state, it counts as one. The same for carbon atoms, the same for buckyballs. And I would then assume the same for basket balls, tardigrades in between, both being also huge bound states of matter. So I even think bangstrom's idea is correct, but the experimental confirmation may lie in a very far future. So I think you should just take the Broglie wavelength of the bound state as a whole. Sadly enough, Wikipedia does not mention the mass of tardigrades... Maybe in the far future we will have amusement parks, where they send you through two doors, so you can experience yourself what it is to go to through 2 doors at the same time. 😉. Why not, you can already experience free fall... Edited October 3, 2022 by Eise
joigus Posted October 3, 2022 Posted October 3, 2022 (edited) 30 minutes ago, Eise said: However, @joigus, I think you make an error in your argumentation. Interference experiments with buckyballs have succeeded. Quote Not surprised. I agreed to that one. Here's what I said: 14 hours ago, joigus said: Now for buckyballs --I guess that's what you mean-- those are fullerene particles very common in interstellar soot, so I'm guessing it's possible in principle, like in the case of silicon atoms, although extremely difficult. I already gave you a reference to macroscopic superpositions of bunches of silicon atoms, but again you missed it. Give us the reference to your Schrödinger water bears, please. I wanna have a good laugh. Water bear = tardigrade Essentially no different from experiment with a number of silicon atoms (the fullerene experiment.) On 9/19/2022 at 1:36 PM, joigus said: The so-called Schrödinger-cat experiments refer to producing quantum superpositions of mesoscopic systems (size bigger than a single elementary particle, but still not daily-life size). The results were published in 2018, it was made with microbeams of silicon 10 micrometers long and 1x0.25 micrometers across, keeping quantum coherence all along. This is the experiment: https://www.nature.com/articles/s41586-018-0036-z There are other: https://phys.org/news/2017-11-physicists-qubit-entanglement.html You can take one qubit, coherently entangle it with another identical qubit, further entangle it with another qubit, and so on. It's an incremental process. I see no problem with that, except technical. Entangle a qubit with a whole bunch of atoms already involved in dissipative --irreversible-- interactions? Impossible. In fact, it doesn't even make sense: What does it even mean to entangle non-identical things? I understand I'm the party pooper here. Some people want to see extraordinary, magical things. Their will to do so takes them on a journey into foolishness and unsupported claims, as well as to drawing conclusions that are not there, and never were. It's all ordinary things. It's the world you see, none other. It's a cat looking at you and being there, alive through and through. Your life passes by before your eyes, and your cat is no longer there, keeping you company, as @MigL knows very well. What I would like some people to see is how magical, how extraordinary, ordinary things are. That's physics' "magic." It takes a while. It doesn't come easy. Edited October 3, 2022 by joigus minor addition
Eise Posted October 3, 2022 Posted October 3, 2022 1 hour ago, joigus said: Not surprised. I agreed to that one. Here's what I said: 15 hours ago, joigus said: Now for buckyballs --I guess that's what you mean-- those are fullerene particles very common in interstellar soot, so I'm guessing it's possible in principle, like in the case of silicon atoms, although extremely difficult. I already gave you a reference to macroscopic superpositions of bunches of silicon atoms, but again you missed it. Give us the reference to your Schrödinger water bears, please. I wanna have a good laugh. Water bear = tardigrade Essentially no different from experiment with a number of silicon atoms (the fullerene experiment.) I know what you said. My point was against how you argued for your position. Counting particles is not of importance, mass, or better momentum, of the bound system is of importance here. 1 hour ago, joigus said: In fact, it doesn't even make sense: What does it even mean to entangle non-identical things? Good point. It were interference experiments, not entanglement experiments. But if bangstrom cannot just deliver tardigrades, but also a source of identical, entangled tardigrades, we could do the experiment. However, I am not sure to look for correlation or anti-correlation. Before I prepare the experiment, I have e.g. to know if tardigrades are bosons or fermions...
joigus Posted October 3, 2022 Posted October 3, 2022 2 minutes ago, Eise said: I know what you said. My point was against how you argued for your position. Counting particles is not of importance, mass, or better momentum, of the bound system is of importance here. 1 hour ago, joigus said: Exactly. Counting particles is beside the point. It's so easy to find examples of many particles in a maximally entangled state. Take any high-atomic number atom. Eg, californium's 4f energy level has 14 entangled electrons. The point is something else. Now, what is that something else? I'll be back. Running out of time now. See my point? Nature has done 4 better than scientists that prepared a 10-silicon-atoms entangled state.
bangstrom Posted October 4, 2022 Posted October 4, 2022 (edited) 22 hours ago, Eise said: No, you turn it around: instead of providing references of QM specialists who see 'real superluminal connections', you provide a link to a physicist who denies none-locality, strengthening my position. Try again. The mainstream view among physicists is that non-locality has been demonstrated as ‘real’ with few contrary opinions such as those of Gell-Mann or Kracklauer. With the exception of those two, the vast majority remaining are the ones that do think non-locality is real. Another commonly held view is that any electron can establish a non-local resonant connection with any other electron on the same light cone with retarded and advanced potentials going both forward and backward in time. Carver A. Mead explains this in his book, “Collective Electrodynamics.” And the same idea can be traced back to the old Wheeler-Feynman Absorber Theory so this is nothing new. The experiments done by Carver Mead or Anton Zeilinger could not work as they do if it were not for non-local interactions. Here is a video by Sabina Hossenfelder about non-locality. https://www.youtube.com/results?search_query=nonlocality%2C+sabina+hossenfelder "Understanding Quantum Mechanics #3 Non-Locality" 22 hours ago, Eise said: I would suggest that you read Feynman's QED: The Strange Theory of Light and Matter. Then you can wonder why the principle of least action seems to work in classical physics (Lagrange formulation of classical physics, Fermat's theorem etc), in relativity, and in QM (QED). E.g. taking Fermat's theorem, how does the light in advance know what is the fastest way between two points? Must be non-locality... . Done read "Feynman's QED and got the T shirt. The mainstream view among physicists is that non-locality has been demonstrated as ‘real’ with few contrary opinions such as those of Gell-Mann or Kracklauer. With the exception of those two, the vast majority remaining are the ones that do think non-locality is real. Another commonly held view is that any electron can establish a non-local resonant connection with any other electron on the same light cone with retarded and advanced potentials going both forward and backward in time. Carver A. Mead explains this in his book, “Collective Electrodynamics.” And the same idea can be traced back to the old Wheeler-Feynman Absorber Theory so this is nothing new. The experiments performed by Carver Mead or Anton Zeilinger could not work as they do if it were not for non-local interactions. Edited October 4, 2022 by bangstrom removed a duplicate entry
joigus Posted October 4, 2022 Posted October 4, 2022 (edited) 3 hours ago, bangstrom said: Here is a video by Sabina Hossenfelder about non-locality. https://www.youtube.com/results?search_query=nonlocality%2C+sabina+hossenfelder "Understanding Quantum Mechanics #3 Non-Locality" You are so confused. Let's take Sabine Hossenfelder's video and read carefully her statements. I'm reproducing here the most important ones with my emphasis: Quote In quantum mechanics, it's more difficult. Just exactly how quantum mechanics is and is not local, that's what we will talk about today. Is and is not local? Mmm. What could she mean? Quote And that appears to be non-local [...] Appears to be? So what then? Is it, or is it not? More: Quote So this is why quantum mechanics is said to be non-local [...] In other words, some people choose to say it is non-local. Quote Quantum mechanics, it seems, forces you to give up on determinism and locality [...] It seems... mmm. Is that a strong statement to you? Here's the killer: Quote Cool, let us build a transmitter, forget our fly cards and travel non-locally from there on. Unfortunately, that does not work. Because, while quantum mechanics, somehow, seems to be non-local with these strong correlations, there's nothing that actually observably travels non-locally [...] If you quote authorities, the least you could do is listen carefully to what they're saying. I get it. Quantum mechanics seems to be non-local. But actually, it is and it is not. That's why some people choose to say it is non-local. Sweet. You could at least listen to the videos you post, @bangstrom Edited October 4, 2022 by joigus added diacritics
joigus Posted October 4, 2022 Posted October 4, 2022 1 hour ago, joigus said: Quantum mechanics, it seems, forces you to give up on determinism and locality [...] (Quoting Hossenfelder.) Of course not: Quantum mechanics forces you to give up on determinism. Period. If you accepted quantum mechanical experimental success, but --in order to save determinism-- accepted some kind --any kind-- of internal determinism to account for it, you would have to give up on locality. Is that clear at long last? Let me guess: No. The problem with the starting sentence is that it opens the gates to a gross misunderstanding, if you remove the essential words "it seems." It's so common a misunderstanding that I don't care how much time I have to spend talking about it as long as the possibility exists that, finally, people who still think this to be the case, are gathered at the gates of quantum heaven at the end of days. This final day you will meet Feynman, Gell-Mann, Sidney Coleman, a repentant Einstein, Bohm, and a repentant Bell --"repentant" for having introduced confusing words in the first place, but redeemed both Einstein and Bell by their accurate and commonly misunderstood respective analyses--, and agree with all of them that quantum mechanics is local. Classical logic, if pressed to account for quantum correlations, would have to be implemented non-locally. But wait a minute, classical logic is not what quantum mechanics is about. End of story. Or is it? There would be a second loophole for the prophets of non-locality. What if the projection postulate is correct? The projection postulate is strongly non-local. It would be a kind of non-locality with zero consequences, by design, because the components of the quantum state that don't carry the actual output of an experiment, must be killed off by decree. Actually, if you think about it, it's no wonder that it entails a non-local prescription: It was designed to implement the fact that real electrons and photons hit the screen at some point. So you introduce definiteness at some point by design. If you remember Bell's theorem, and really understand it, there is no mystery. And that's all. If bangstrom finally has understood this point, we could perhaps proceed from there. The explanation of that monumental fiction: Why does the projection postulate introduce a non-local prescription that produces no non-local consequences? But something tells me we're not getting there any time soon. This would make for an interesting topic of debate on (bare evidence) + (bare assertions of a theory) vs (epistemological prejudices) of people: Illusion of design --evolution--, illusion of non-locality --QM--, and probably more. The theme is more general than it looks.
Eise Posted October 4, 2022 Posted October 4, 2022 (edited) 2 hours ago, joigus said: You could at least listen to the videos you post, @bangstrom It is even worse. @joigus, Sabine H has a blog, in which she spells out her videos, so you can read them in your own tempo. Here is the one of that video. And this is even 'worse' than what you quoted: Quote So, oddly enough, quantum mechanics is entirely local in the common meaning of the word. When physicists say that it is non-local, they mean that particles which have a common origin but then were separated can be stronger correlated than particles without quantum properties could ever be. I know this sounds somewhat lame, but that’s what quantum non-locality really means. And in the comments. A commenter: Quote If the observed correlations are greater than those allowed by the theory of quantum mechanics, then it is a misnomer to say that (the theory of) quantum mechanics is nonlocal. Sabine Hossenfelder: Quote Wot? The correlations are greater than those allowed by a deterministic, local theory, not by quantum mechanics. Next try! 6 hours ago, bangstrom said: The mainstream view among physicists is that non-locality has been demonstrated as ‘real’ with few contrary opinions such as those of Gell-Mann or Kracklauer. With the exception of those two, the vast majority remaining are the ones that do think non-locality is real. You keep repeating this. But my list becomes longer... Susskind Gell-Man Kracklauer Sidney Coleman (thanks, Joigus) Sabine Hossenfelder 2 Names added on the list thanks to your references... For clarity, let's take the following 3 propositions QM does not allow for FTL causation. Watch my wording: causation. So no signal, (inter)action, affect, or whatever. The conclusion of Bell's theorem is: no local hidden classical system can reproduce the correlations predicted by QM. These correlations were experimentally confirmed, so QM is right. Conclusion: the experiments can be explained by QM, without needing non-locality. Classically, we would need non-locality. So find an acknowledged author that rejects one of the 3 presumptions that together support that QM is local. If you keep repeating that the mainstream think QM is non-local, then it should be easy. But be careful not to shoot yourself in the foot again. Edited October 4, 2022 by Eise 1
studiot Posted October 4, 2022 Posted October 4, 2022 (edited) 7 hours ago, bangstrom said: The mainstream view among physicists is that non-locality has been demonstrated as ‘real’ with few contrary opinions such as those of Gell-Mann or Kracklauer. With the exception of those two, the vast majority remaining are the ones that do think non-locality is real. I haven't post much in this thread as I view it as a non-argument. However can you tell me how and why those two sentences of yours from your last post do not directly contradict each other ? 1) says "The mainstream view is that non locality has been demonstrated" 2) says " the vast majority do not think non-locality is real" Edited October 4, 2022 by studiot
Eise Posted October 4, 2022 Posted October 4, 2022 Hurray! Clauser, Aspect and Zeilinger got this year's Nobel prize!😃 Now the newspapers will be full of articles saying that they have proved non-locality with their experiments.🤪
joigus Posted October 4, 2022 Posted October 4, 2022 2 hours ago, Eise said: Conclusion: the experiments can be explained by QM, without needing non-locality. Classically, we would need non-locality. So find an acknowledged author that rejects one of the 3 presumptions that together support that QM is local. If you keep repeating that the mainstream think QM is non-local, then it should be easy. But be careful not to shoot yourself in the foot again. Very good post, Eise. +1 You certainly bring clarity into the question, and perfectly understand the logical points. You say you're not totally familiar with the formalism, but still. And thanks for the reference to Hossenfelder's blog. And that Nobel Prize is well deserved for Clauser, Aspect, and Zeilinger. 46 minutes ago, Eise said: Now the newspapers will be full of articles saying that they have proved non-locality with their experiments.🤪 Oh, be in no doubt!
bangstrom Posted October 5, 2022 Posted October 5, 2022 9 hours ago, studiot said: 16 hours ago, bangstrom said: The mainstream view among physicists is that non-locality has been demonstrated as ‘real’ with few contrary opinions such as those of Gell-Mann or Kracklauer. With the exception of those two, the vast majority remaining are the ones that do think non-locality is real. I haven't post much in this thread as I view it as a non-argument. However can you tell me how and why those two sentences of yours from your last post do not directly contradict each other ? 1) says "The mainstream view is that non locality has been demonstrated" 2) says " the vast majority do not think non-locality is real" There was no do "not" in my statement so the statements do not contradict. The "not" is your addition. 9 hours ago, Eise said: It is even worse. @joigus, Sabine H has a blog, in which she spells out her videos, so you can read them in your own tempo. Here is the one of that video. And this is even 'worse' than what you quoted: Quote So, oddly enough, quantum mechanics is entirely local in the common meaning of the word. When physicists say that it is non-local, they mean that particles which have a common origin but then were separated can be stronger correlated than particles without quantum properties could ever be. I know this sounds somewhat lame, but that’s what quantum non-locality really means. The first sentence reads, "So, oddly enough, quantum mechanics is entirely local in the common meaning of the word." OK, there is locality in the “common” meaning of the word but physicists have a deeper understanding of the events in which the observed events are non-local. That's what QM really means as Hossenfelder explains in the the next sentence. "When physicists say that it is non-local, they mean that particles which have a common origin but then were separated can be stronger correlated than particles without quantum properties could ever be. I know this sounds somewhat lame, but that’s what quantum non-locality really means." You are reading something into the quotes that is not there. 10 hours ago, Eise said: For clarity, let's take the following 3 propositions QM does not allow for FTL causation. Watch my wording: causation. So no signal, (inter)action, affect, or whatever. The conclusion of Bell's theorem is: no local hidden classical system can reproduce the correlations predicted by QM. These correlations were experimentally confirmed, so QM is right. Conclusion: the experiments can be explained by QM, without needing non-locality. Classically, we would need non-locality. 1. Non-locality (FTL) does not imply causation. 2. Is OK 3. The correlations are confirmed and can be explained classically. The coin flips for example. Correlations are not exclusively a property of QM so the observation of correlations supports the classical view as well. In QM the absence of determinism prior to the first measurement (ruled out by the Bell test) can not be explained without non-locality.
bangstrom Posted October 5, 2022 Posted October 5, 2022 13 hours ago, joigus said: Quantum mechanics, it seems, forces you to give up on determinism and locality [...] In QM, the quantum properties are indeterminate prior to the first observation. Experimental results showing a violation of the Bell test have done away with determinism and locality. Non-locality in QM remains as the default explanation. 10 hours ago, Eise said: If the observed correlations are greater than those allowed by the theory of quantum mechanics, then it is a misnomer to say that (the theory of) quantum mechanics is nonlocal. Sabine Hossenfelder: Where did this quote come from? It looks bass ackward to me. In tests of Bell's inequalities the QM model predicted more possible correlations than the classical model. Can someone verify the quote?
bangstrom Posted October 5, 2022 Posted October 5, 2022 17 hours ago, joigus said: Quote Cool, let us build a transmitter, forget our fly cards and travel non-locally from there on. Unfortunately, that does not work. Because, while quantum mechanics, somehow, seems to be non-local with these strong correlations, there's nothing that actually observably travels non-locally [...] If you quote authorities, the least you could do is listen carefully to what they're saying. I get it. Quantum mechanics seems to be non-local. But actually, it is and it is not. That's why some people choose to say it is non-local. Sweet. Sabina H. is saying in the quote above that non-locality does not work at the macro level so we can’t fly from place to place non-locally. In other words, it doesn’t work like teleportation on ‘Star Trek’. There is nothing “observably” traveling non-locally. If we could observe something traveling from point to point it would necessarily be traveling locally. Non-locality implies that there is no observable transition in the points between. 15 hours ago, joigus said: And that's all. If bangstrom finally has understood this point, we could perhaps proceed from there. The explanation of that monumental fiction: Why does the projection postulate introduce a non-local prescription that produces no non-local consequences? The quantum properties are indeterminate and non-local prior to the first observation, and with that, the loss of entanglement. That is when the eigenstates appear and, from that point on, observations and consequences are local. 17 hours ago, joigus said: If you quote authorities, the least you could do is listen carefully to what they're saying. I get it. Quantum mechanics seems to be non-local. But actually, it is and it is not. That's why some people choose to say it is non-local. Sweet. You could at least listen to the videos you post, @bangstrom I don’t see how your view that QM is local can be found in the video. Here is another quote from Sabina H. “So this is why quantum mechanics is said to be non-local. Because you have these correlations between separated particles that are stronger than they could possibly be if the state had been determined before measurement. Quantum mechanics, it seems, forces you to give up on determinism and locality. It is fundamentally unpredictable and non-local.” 4 hours ago, bangstrom said: Where did this quote come from? It looks bass ackward to me. In tests of Bell's inequalities the QM model predicted more possible correlations than the classical model. Can someone verify the quote? I see now the quote was from a commenter outside this forum, but still, it looks bass ackward.
joigus Posted October 5, 2022 Posted October 5, 2022 4 hours ago, bangstrom said: Where did this quote come from? It looks bass ackward to me. In tests of Bell's inequalities the QM model predicted more possible correlations than the classical model. Can someone verify the quote? Quote Greg Feild9:18 AM, May 30, 2020 If the observed correlations are greater than those allowed by the theory of quantum mechanics, then it is a misnomer to say that (the theory of) quantum mechanics is nonlocal. I know this is how people talk, but technically, grammatically, it seems incorrect ... http://backreaction.blogspot.com/2020/05/understanding-quantum-mechanics-3-non.html There. It took me a couple of seconds. That's what it takes when you actually read what people are telling you.
bangstrom Posted October 5, 2022 Posted October 5, 2022 5 minutes ago, joigus said: There. It took me a couple of seconds. That's what it takes when you actually read what people are telling you. Did you actually read it? It ain't there.
joigus Posted October 5, 2022 Posted October 5, 2022 (edited) 1 hour ago, bangstrom said: I don’t see how your view that QM is local can be found in the video. Here is another quote from Sabina H. Of course, you don't. How could you? Quote So, oddly enough, quantum mechanics is entirely local in the common meaning of the word. Sabine Hossenfelder http://backreaction.blogspot.com/2020/05/understanding-quantum-mechanics-3-non.html You're welcome. I disagree with Hossenfelder that it's difficult or "complicated." I think it's obvious if you pay attention to some arguments people have presented here. 8 minutes ago, bangstrom said: Did you actually read it? It ain't there. Are you familiar with Ctrl+F? There are 153 comments. I hope you're not looking for it by skimming through the text! 1 hour ago, bangstrom said: I see now the quote was from a commenter outside this forum, but still, it looks bass ackward. It's not. Believe me. Edited October 5, 2022 by joigus minor correction
bangstrom Posted October 5, 2022 Posted October 5, 2022 22 minutes ago, joigus said: Are you familiar with Ctrl+F? There are 153 comments. I hope you're not looking for it by skimming through the text! I am not familiar with Ctrl+F and I did read through the entire transcript of the video and the quote wasn't there. It was six feet down in the comments which I didn't bother to read. I found the origin of the quote and Sabina's quote, "Wot? The correlations are greater than those allowed by a deterministic, local theory, not by quantum mechanics." and that did confirm my suspicion that the comment was in reverse of her claim in the video. Unfortunately, it was not clear from the original post who was saying what. 33 minutes ago, joigus said: 1 hour ago, bangstrom said: I don’t see how your view that QM is local can be found in the video. Here is another quote from Sabina H. Of course, you don't. How could you? I followed the video, What is your excuse? You must have an entirely different definition of 'non-locality' from mine which I defined earlier. So I will ask again, How do you define 'non-locality'? Also, you said quantum teleportation is a misnomer from what it is "actually" So I will ask again, What is quantum teleportation "actually" or at least explain why you think it is a misnomer?
studiot Posted October 5, 2022 Posted October 5, 2022 8 hours ago, bangstrom said: There was no do "not" in my statement so the statements do not contradict. The "not" is your addition. You are completely correct. I don't know what made me think there was , I checked several times and thought there was. My sincere apologies. 😳
joigus Posted October 5, 2022 Posted October 5, 2022 1 hour ago, bangstrom said: I followed the video, What is your excuse? I made no mistake or omission, therefore no excuse is needed on my part. 1 hour ago, bangstrom said: You must have an entirely different definition of 'non-locality' from mine which I defined earlier. So I will ask again, How do you define 'non-locality'? Read back. @Eise gave a quite economic, quite satisfactory one I agreed to. I gave at least two more mathematical ones and referred to them later when asked. But because mine are perhaps too technical --although perfectly mainstream--, I'm OK with Eise's. All are equivalent and it can be shown mathematically in terms of a so-called Cauchy problem. I can do my best to help people understand or clarify possibly obscure points, but I do not condone laziness.
Eise Posted October 5, 2022 Posted October 5, 2022 1 hour ago, bangstrom said: I found the origin of the quote and Sabina's quote, "Wot? The correlations are greater than those allowed by a deterministic, local theory, not by quantum mechanics." and that did confirm my suspicion that the comment was in reverse of her claim in the video. Yep, exactly what I wanted to show here: Sabine H says it very clearly: The correlations are greater than those allowed by a deterministic, local theory, not by quantum mechanics. So in QM the correlations are local. 7 hours ago, bangstrom said: The first sentence reads, "So, oddly enough, quantum mechanics is entirely local in the common meaning of the word." OK, there is locality in the “common” meaning of the word but physicists have a deeper understanding of the events in which the observed events are non-local. That's what QM really means as Hossenfelder explains in the the next sentence. "When physicists say that it is non-local, they mean that particles which have a common origin but then were separated can be stronger correlated than particles without quantum properties could ever be. I know this sounds somewhat lame, but that’s what quantum non-locality really means." You are reading something into the quotes that is not there. Sorry, the error is yours. Your interpretation is wrong. Compare with all citations @joigus made from the video, in which words like 'seems', 'appears', 'says' are heavily used. And in the sentences you cited, she sets the records straight. In QM there are no non-local causes/signals/information transfer/affects. I even just discovered that for my point 1 (of the three points above) has an official name: the no-communication theorem: Quote In physics, the no-communication theorem or no-signaling principle is a no-go theorem from quantum information theory which states that, during measurement of an entangled quantum state, it is not possible for one observer, by making a measurement of a subsystem of the total state, to communicate information to another observer. The theorem is important because, in quantum mechanics, quantum entanglement is an effect by which certain widely separated events can be correlated in ways that, at first glance, suggest the possibility of communication faster-than-light. The no-communication theorem gives conditions under which such transfer of information between two observers is impossible. These results can be applied to understand the so-called paradoxes in quantum mechanics, such as the EPR paradox, or violations of local realism obtained in tests of Bell's theorem. In these experiments, the no-communication theorem shows that failure of local realism does not lead to what could be referred to as "spooky communication at a distance" (in analogy with Einstein's labeling of quantum entanglement as requiring "spooky action at a distance" on the assumption of QM's completeness). My italics. So what is left? Correlation. And correlation can be faster than light even classically: that is the example of the left and right hand shoes. Condition is that the correlated 'events': opening the boxes; measuring spins, have a common history. And that they both have. Putting the two shoes in the boxes; creating two entangled particles. The only astonishing is that the correlation in QM is stronger than in classical mechanics. That definitely has a 'FTL odour'. But 'odour' is just as a physical concept as 'spooky', namely none. 8 hours ago, bangstrom said: 1. Non-locality (FTL) does not imply causation. 2. Is OK 3. The correlations are confirmed and can be explained classically. The coin flips for example. Coin flips can be explained classically. QM correlations cannot. And further I am still waiting of citations of authoritative QM experts that say that in QM there is 'spooky xxx' at a distance. So no simple text books, these are already critisised by Sidney Coleman. So reference to authorities, please. And of course no popular science books.
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