Eise

8 minutes ago, LaurieAG said:

There is a gap in posts between 5 hours ago (4 hours on the image in your post) and last Monday at 7:25 am (it is Thursday now) so you should assume that something was wrong with the site for 3 days.

Exactly, that's why I posted it.

Hi administrators,

For 3 days I could not reach these forums. As I see no postings telling us what happened, must I assume it was not a problem at science forums itself? I could not connect from my work, and neither from my home. The error suggested that the URL could not be resolved. Was this a local problem? Swiss? European? Or was it really some problem with the URL registration?

I was already desparately trying to find somebody I could contact to find out what was going wrong (WHOIS, trying to find out the email address of one of the moderators). SF is one of my daily mental vitamins. 

Glad to see y'all back again!

Eise

PS My, lucky enough very small conspiracy theory module, thought already that it concerned my posting about trackers... 

PPS At least there seems to be a time gap:

26 minutes ago, bangstrom said:

at least 10,000 times faster than light

Psst... It is faster than thought...

Because I have problems with my stone age old Ubuntu, and with that, with the installed browsers, I sometimes have to change from Opera to Firefox. I nearly always use Opera, but using Firefox, with my add-ons, I saw there are quite a few trackers on scienceforums:

Is this just in the forum software package, i.e. unremovable? Or is it part of a sponsoring contract? If possible, I of course would like them removed. Otherwise, I assume we have to accept this. I have "do not track" set, but AFAIK it just sends a request not to be tracked, it does not block trackers.

2 hours ago, bangstrom said:

You asked for a QM citation and not just my personal opinion and you and you got it.

I think Swansont asked for a QM derivation, not for citations:

20 hours ago, swansont said:

And I asked for QM, not an article about QM

Which of "not an article about QM" you did not understand?

In the hope I correctly understand Swansont's Ansatz, he is doing the following. He gives you the formula which rolls out of the math of QM. I hope you recognise it. Joigus also mentioned it (I think even a few times). The importance of the formula in this context is that it does not contain a dependency of the distance between the measurements, i.e. it is valid even if the measurements are space-like separated. So your task is to show the formula wrong.

2 hours ago, bangstrom said:

It's not part of which theory? QM, EPR, classical?

QM. Just QM.

2 hours ago, bangstrom said:

My views about about entanglement can be found in this simple article.

Your citation contains no description of the question 'locality or realism'. I think it also contains nothing Swansont would disagree with. So this article might be a correct description of entanglement, but it is not relevant.

2 hours ago, bangstrom said:

I find the views expressed here so far about quantum entanglement to be outdated and quite contrary to the mainstream consensus (not that that makes them wrong).

The IBM lady you have called as witness, disagrees with you. The video is less than 50 years old...

2 hours ago, bangstrom said:

I am inclined to ask, if entanglement is not non-local and nothing unusual or anything that can not be described as classical or a violation of the EPR effect, then why did the Big Three ACZ win the Nobel for discovering something so ordinary?

Because, from a classical view, the results are outrageous. Two of the fundamental assumptions of classical physics are challenged, locality and realism (in the technical sense of those words, not of your vague interpretations of them, see CHSH). There obviously were physicists that trusted QM so much, that they did not find it necessary to do such experiments, e.g. Feynman. He was not interested in Clauser's experiment. And Zeilinger's experiments also lead the way to applications of entanglement: quantum cryptography, quantum teleportation and quantum computing. You did read the articles on the Nobel prize website, didn't you? But of course you did not understand them.

2 hours ago, bangstrom said:

“The word “entanglement” was first used by physicist Erwin Schrödinger (one of the pioneers of quantum mechanics). He explained quantum entanglement as one of the fundamental features of quantum mechanics. He said that its presence is an absolute deconstruction of classical mechanics or physical logic.”

Hm. Reminds me of a posting here...

2 hours ago, bangstrom said:

Entanglement demonstrates the presence of some kind of 'signaling', for the lack of a better word, between remote particles where an observation of one particle non-locally affects it's entangled partner.

And another foot shot. From the same article:

Quote

Importantly, there is also no conflict with special relativity, which forbids faster-than-light communication. The fact that measurements over vast distances are correlated does not imply that information is transmitted between the particles. 

Italics and bold by me.

2 hours ago, bangstrom said:

I underlined the last part and how is that different from what I said in my quote above?

You redefined 'realism', so that it contains 'locality'. But your IBM speaker clearly distinguishes in a very technical way between the two, namely as the only two assumptions of the CHSH inequality.

You've made clear for all of us:

• You cannot understand the argumentative arc of texts
• And related, you cite pieces of texts that seem to support you viewpoint, but in fact the text as a whole does not
• You are not able to refer to a modern article (less than 50 years old, if you know what I mean) of a respectable physicist that defends that of the two, locality and realism (in their technical sense, not in your unjustified interpretation of it), we have to give up on locality
• You do not understand how we use special relativity to argue that there is no direction in the correlation of Alice's and Bob's measurements
• You do not even understand special relativity
• And last but not least, you simply do not understand quantum mechanics.

I think we should close the thread. Because of Joigus' mental health 😉, and my ability to express my free will (didn't I say I am out?) 😟, and because of this:

And I found this elaborate extension of it:

4 hours ago, bangstrom said:

When entanglement is lost, it is lost instantly across both ends of the wave function and experiments have demonstrated that the changes to one particle are simultaneous with changes other particle. This is why the interaction is considered to be non-local and FTL. Since no physical connection is involved, that is what Einstein called “Spukhafte Fernwirkung” and he thought, That can't be right.

No need anymore to comment on this.

4 hours ago, bangstrom said:

That is the 'realism' we have to give up.

But then, we see how you bend what is said, even in your video. At 7:55 she says that the only two assumptions that went into the CHSH inequality are locality and realism. See the screenshot I made from the video.

So it is locality or realism (or both) that we must give up. And to repeat: later on she says "The way that most scientists have interpreted this, is that we have to give up on the idea of realism".

1 hour ago, bangstrom said:

Why do you think I don’t understand? Initially, Alice think she is first and Bob thinks he is first but it maks nix.

Fully agree with Joigus. You just showed that you do not understand one single word that MigL, Joigus and I said when considering relativity in such entanglement experiments. And Joigus made such a beautiful drawing, exactly showing what I meant (+1).

You are nearing the troll-zone. Instead of sticking to your viewpoint, try to understand what here is said. Please do.

21 hours ago, bangstrom said:

"Bells Inequality: the weirdest theorem in the word | Nobel …"

https://www.youtube.com/watch?v=9OM0jSTeeBg

It is really amusing to see how you shoot yourself in the foot again and again. At about 10:05:

Quote

The way that most scientists have interpreted this, is that we have to give up on the idea of realism

2 hours ago, bangstrom said:

I haven’t been ignoring the “suggestion”. I just don’t follow the practices here of saying you are wrong and confused and your idea is garbage if I disagree.

It is not garbage, in the end even a lot of physicists thought we have to give up on locality. See my citation of Zeilinger from his Dance of the photons. But his book is from 2010. Now 12 years later, in 'your video', above is said. So it seems  the consensus is moving in the other direction.

Your counter argument against my relativity however, is garbage, as @joigusalso noted.

9 hours ago, bangstrom said:

You are right right. That is a perfectly good explanation for correlation and there are many experts who would agree with you. Hold that thought and consider the implications.

I did. In my opinion (maybe Swansont, Joigus, and MigL would not agree, that's why I say 'opinion') that in QM, more specifically the wave function, we have reached the limit of our our capacity to know and understand nature. In a Kantian way, one could say that we encountered the limit behind which the thing-in-itself (Ding-an-sich) is hiding. I have a hunge (even more vague than 'opinion'), that there will be no new experiments that will close some of the remaining interpretations (MWI, superdeterminism (of which Sabine Hossenfelder is a fan), counterfactual definiteness). But more Zeilingers will stand up, and will design more unbelievable applications of entanglement. And who knows, some day my hunge and opinion turn out to be wrong?

Can you tell us, why you are so attached to the idea of non-locality? Or what you have against loosening our conception of realism? You see, the moon really is there, even if we do not look up. But we cannot observe the wave function. It is only at this very deep level we must loosen our concept of realism, not in our daily life.

4 hours ago, bangstrom said:

However, if two events happen at exactly the same time...

OK, so we assume that in the reference frame of Alice, the source of entangled particles exactly in the middle, and Bob on the other side; nobody is moving against each other. So if Alice and Bob find a correlation between their measurements, it is impossible to say who was first. That is already problematic for you: in which direction is the signal/information/communication/effect/action/interaction going? The situation is exactly symmetrical.

Now observer1 flies with great speed from Alice to Bob. He will see that one of them was before the other, and could conclude that one sent a signal to the other.

Observer2 flies in the opposite direction, from Bob to Alice, and so concludes exactly the opposite, she will say that the other one was first.

If Observer1 and 2 know their relativity, they will recognise that the events are space-like separated, and the correlation must be caused by an event that exists in the respective light cones of Alice and Bob. And lo and behold, there is a one single source of entangled particles in the light cones of both. So the reason of the correlation lies in the past that Alice and Bob share. Like a pair of shoes... There is no signal/information/communication/effect/action/interaction needed to explain this correlation.

I have a dejà vu.

3 hours ago, bangstrom said:

The experiments of Bell, Aspect, and Clauser demonstrated that...

Another dejà vu... Bell did not do these kind of experiments. I assume you mean Zeilinger. You know, one of the three that got a Nobel prize.

4 hours ago, bangstrom said:

But it is possible to say which came first before that. Just ask the experimenters which observation they chose to measure first.

It seems that you also do not understand special relativity. There is no preferred frame of reference. So in space-like separated events, there will be an observer for whom Alice's measurement occurred before Bob's, and also an observer for whom Bob's measurement was before Alice's. The frames of reference of the source, or of Alice or Bob simply are not  preferred frames of reference, because there are none. I thought MigL was very clear about it, and I also brought this point when I referred to this Geneva experiment the first time, but it seems you do not understand it.

7 hours ago, bangstrom said:

Bell, Aspect and Clauser won the Nobel prize for demonstrating that the first signal was both not fixed from the start and also that it was superluminal.

Bell is, pity enough, dead, so he did not get a Nobel prize. You mean Clauser, Aspect, and Zeilinger.

And Zeilinger himself says in the book you introduced here in the discussion, that he thinks that of our presuppositions, we have to give up on reality, not on locality. Others, see my list of authors, take an even stronger position. QM is local.

And do you realise you really did not answer Swansont's question? 

11 hours ago, swansont said:

How can Bob read a signal before it gets to him?

You are talking around it, without answering the question.

2 hours ago, bangstrom said:

That must be some ancient ‘fact’ you favor because you don’t appear to be aware of anything recent.

Bullshit. Don't ever say this again. Or better show us where Joigus and Swansont are not uptodate, and you are.

Addition:

For what it is worth, the publication years of the sources of my 'authority list':

• Coleman:1994
• Kracklauer: 2002
• Zeilinger: 2010
• Susskind: 2015
• Gell-Man: 2016
• Hossenfelder: 2020

5 hours ago, bangstrom said:

In one observation, we can know that one quantum property of particle B, has gone from indeterminate to determinate.

But nothing on Bob's side shows him that the particle has an entangled partner.

OK, if you really need reading help, I am not such a bad guy.

- - - - - - 

1 hour ago, bangstrom said:

Nearly all physicists agree that the experiments have shown that local realism is an untenable position

Nearly all physicists agree that the experiments have shown that either locality or realism, or both, must be given up.

1 hour ago, bangstrom said:

The viewpoint of most physicists is that the violation of Bell’s inequality shows us that quantum mechanics is nonlocal.

Most physicists think that we must give up on locality.

1 hour ago, bangstrom said:

This nonlocality is exactly what Albert Einstein called “spooky’; it seems eerie that the act of measuring one particle could instantly influence the other one.

That is exactly what Einstein meant, and called 'spooky'. It seems weird that when one measures one particle, it immediately influences the other one.

- - - - - - 

But take care!  In the next paragraph, Zeilinger speaks for himself, not for 'most physicists'. And there he clearly says, that he thinks we should drop realism, not locality.

Wrong again:

2 hours ago, bangstrom said:

The no-communication theorem says you can not clone quantum properties

The no-clone theorem and the no-communication theorem are two different results derived from QM.

2 hours ago, bangstrom said:

Zeilinger then goes on to explain how later more precise experiments confirmed that local realism was violated confirming non-locality.

Nope. Yes, he says that local realism is violated, but as MigL already said (and Joigus, and Zeilinger) that means that either:

• locality is violated, or
• realism is violated,
• or both of course.

Zeilinger tends to giving up on realism.

That's it. I won't react on all your other concept- and word bending misinterpretations. Learn reading, and then QM.

I forgot this one:

2 hours ago, bangstrom said:

Quoting passages serves two purposes. It allows me to reexamine my personal views to see if they actually conform to what I think author says

What you are really doing is picking citations, that confirm your pre-existing belief, out of context without understanding the overall argumentation.

Sorry, @bangstrom, but now you crossed the border of an honest, argumentative discourse. I assume you have some ideological reasons, and that your ideology needs non-locality. Otherwise I cannot explain the huge misses you make here, and your derogation of Joigus' and Swansonts knowledge of QM.

3 hours ago, bangstrom said:

The no-communication theorem deals with FTL communication at the macro level but not at the quantum particle level. That is a different issue.

The no-communication theorem is derived from the formalism of QM, and is valid on all levels.

5 hours ago, bangstrom said:

We can’t observe the wave function but we can observe the changes that appear after the wave function is lost.

If you observe something only one time, you cannot conclude that it has changed. In Bell-like experiments, Bob from his side does not notice anything special. He just gets random results, as if he is just doing experiments on some simple particle source. Only when Alice and Bob compare their lists (these cannot be send FTL), they notice that the correlations are stronger than any classical system allows.

5 hours ago, bangstrom said:

Swansont’s claims like those of joigus may be logical and consistent with the EPR effect but they are 50 years behind what we now understand about QM.

On the contrary. The problem is you do not understand modern QM. Einstein objected against the non-local 'odour' of QM, but since then, physicists have developed QM further, and e.g. came up with the no-communication theorem, which excludes any FTL communication (and effect, and influence, and ...).

5 hours ago, bangstrom said:

The EPR effect was invalidated long ago by the Bell test and has been repeatedly invalidated ever since.

Invalidated? On the contrary, the conclusion of the article that seemed contradictory to relativity, was confirmed by Bell-like experiments: the QM depiction of the world that Einstein thought was too absurd to be true, turns out to be true.

5 hours ago, bangstrom said:

Most notably by those who just won the Nobel.

And still Zeilinger would rather give up realism than locality. That is clear if you would really read his book, understand his argumentation, instead of citing passages from his book that seem to support your position.

5 hours ago, bangstrom said:

Agreed, it is interpretation- not influencing-  but that still that makes Alice an agent of change whether the experiment involves going forward or backward in time.

Nope. Read, and understand what Zeilinger is saying: in short, if Alice does here measurement before or after Bob did, it describes two different experiments, which means different boundary conditions. As said before, of the five ways Zeilinger mentions that could explain Bell-like experiments, Zeilinger dismisses 'back in time propagation', instead refers, to the fact that they are different experiments. Maybe this has a connection, or is even an example of 'contextuality' as meant in the Kochen-Specker theorem? @joigus: do you  think that is correct?

5 hours ago, bangstrom said:

Experts in any field rarely discuss the long established basics of their work so quotes from experts are hard to find. That job is left to the second tier experts and science journalists.

So no outrage about the position of Gell-Mann, Susskind, Kracklauer, Sidney Coleman, etc.? In short, you are not able to show an authoritative text, that pleads for giving up locality instead of realism.

4 minutes ago, bangstrom said:

I would say we still have local reality for non-entangled particles but non-locality and instant action at a distance for entangled particles.

Sigh... Using 'action' again.

5 minutes ago, bangstrom said:

Perhaps non-locality is not implied, but non-locality is the best alternative and it works when needed.

'My experts' disagree with you, and Zeilinger explicitly prefers to give up on realism, instead of locality.

8 minutes ago, bangstrom said:

The thing to note here is that the later entanglement of C with B to create the entangled state (CB) makes (CB) a sort of ‘teleporter’ such the the quantum state of C also becomes the quantum state of A. To a naive observer of the events, it appears that particle C enters the (CB) ‘teleporter’ and instantly appears at the remote location A. This sort of identity swapping violates both local realism and relativistic causality which are based on macro level observations but they do not apply to what is observed with entangled particles.

I am afraid, you forgot again, that teleportation needs an additional classical communication channel.

I think I am done here. Unless a Bell-Kochen-Specker-Bangstrom inequality is derived that can distinguish if we must abandon locality, and not realism, (and empirically tested of course), I rest my case.

Your ideological glasses make you blind, blind as two perpendicular oriented polarisators behind each other.

3 hours ago, bangstrom said:

But, if an event in one location instantly changes an event in a distant location with no apparent connection, the action is non-local.

You should better take care of your words, which is very important in such fundamental questions. I made them italic:

• action: we had this again and again. There is no action, no interaction, no causal relationship, no information transfer, no affect, no influence between the measurements. These are all excluded by the no-communication theorem.
• change: there is no change, in the first place because a change needs a cause, and that is already done away with with the previous point. In the second place, we cannot detect this change, because we cannot observe the wave function itself. We cannot look deeper then individual quantum  measurements, and therefore we can only detect correlations.

9 hours ago, bangstrom said:

This is the mainstream explanation again and you can take it or leave it, or better yet, look it up for yourself. It is easy to find.

This is hubris. Swansont knows more about QM than you, me, and Joigus together.

You are referring to the mainstream again. And still, you are not able to mention any QM expert precisely arguing why it is that we have to give up locality in QM.

3 hours ago, bangstrom said:

”The interesting point is that in the end we will, for Bob’s results, present a different interpretation depending on what Alice at a later time decides to do. She may decide to do a Bell-state measurement, or she might decide to do a measurement on each photon on its own, there is even an infinite zoo of possibilities in between. Depending on what Alice decides to do, the results registered earlier by Bob, the events that already happened, acquire a very different meaning."

Again you do not understand quite what Zeilinger is saying here, and his viewpoint later in the chapter. I italicized the words. Zeilinger does not talk about events 'influencing' events in the past. He is saying that our interpretation of the experiment is different. Alice's measurement occurring before Bob's measurements, or after his measurements are different experiments, i.e. we need different interpretations of the experimental situation.

Quote

At this point,we might state one point with emphasis. Each of the interpretations we come up with for Bob’s earlier results is completely correct and objective. The fact that an interpretation depends on Alice’s future decision does not at all make it incorrect or subjective. Quantum physics describes all of these situations well. It is just that the mathematical description, the quantum state we assign to the situation, is very different depending on what Alice decides to do. It depends on the specifics of the experimental settings, and therefore, it depends on Alice’s decisions, or in general it depends on the decisions of us as experimenters. And this may include specifics of the experiment that will be decided in the future.

Emphasis by me. And then:

Quote

These kinds of considerations support the point of view that has most succinctly been  expressed in the Copenhagen Interpretation of quantum physics as it was created specifically by Niels Bohr. According to that interpretation, the quantum state of a system is not a field, or some entity that spreads “out there” in space and time. On the contrary, the quantum state is  just a representation of the knowledge we have of the specific physical situation we are investigating. This representation of our knowledge naturally depends on which situation we  have in front of us, which kinds of measurement results we obtain.

And then, more specific:

Quote

In our specific case, our knowledge of the specific situation depends on the kind of measurement Alice performs at a later time and the result she obtains then. We conclude that Alice’s later measurement, and her result, do not influence the physical reality already in existence—namely, the specific results Bob obtained at an earlier time. But they change what we may say about the situation. They change our interpretation of what is going on. This very much calls to mind a famous statement by Bohr: “There is no quantum world. There is only an abstract quantum physical description. It is wrong to think that the task of physics is to find out how nature is. Physics concerns what we can say about nature.”

Italics by me.

The obvious problem for you is that Zeilinger is a nice and reasonable fellow. So he presents different viewpoints and mentions a few arguments pro and contra these viewpoints. And then you pick out the arguments that fit to your viewpoint. But giving his own viewpoint Zeilinger is very clear: on QM level, we have to depart from realism; not locality.

2 hours ago, bangstrom said:

From my reading he appears to be leaning in favor of actions to the past

I showed you above that this is not his opinion.

And you are using 'action' again!

2 hours ago, bangstrom said:

Where does Zeilinger dismiss #5? 

(...)

"Another logically possible position would be to presume that the individual particles act back into the past, From that point of view, they would influence the the source, back in the past, with which properties to emit each particle. It is again obvious that such a position would mean a very radical rewriting of our views of space and time."

Underlined it for you. Sure, he does not say this is excluded, but that giving our present insights it is not the best solution, because it would mean a total rewriting our present understanding.

It is also, clear from the context in which he discusses this, taking the options 4 and 5 behind the sentence:

Quote

Just for completeness, let us mention that some other positions are also possible, at least in principle.

Meaning 'to be honest, there are two other interpretations, but I do not take them seriously'.

You really have a problem understanding texts.

16 hours ago, bangstrom said:

I understand that to mean that that we can abandon locality at the single particle level. Obviously that does not mean that we are forced to abandon locality altogether.

With a single particle, entanglement of course plays no role at all. Which is what Zeilinger says:

Quote

Now, since Kochen and Specker only considered measurements on single quantum particles, the locality hypothesis does not come into play.

But Zeilinger uses it in his argumentation for his view. Look how he is doing it:

Zeilinger discusses 5 ways out after the confirmation that QM violates the Bell inequalities.

1. Deny realism
2. Deny locality
3. Deny counterfactual definiteness
4. Accept superdeterminism
5. Accept actions to the past

He more or less discards 3 4, and 5 rather briskly. Of locality, as already cited early, he remarks that most physicists think that we should give up on locality. However he tends to give up on realism, because this seems to be the conclusion of the Kochen-Specker theorem, and its first empirical tests. So the KS theorem has directly nothing to do with Bell states. But for Zeilinger it is a hint that of 'local realism' (which, as Joigus explained means 'locality' and 'realism' taken together), we have to loosen our concept of a reality behind our quantum measurements.

Please reread the chapter 'What could that mean?'. (Warning: he does not discuss these in the exact order as I did here. I streamlined his argument here. First he mentions the first three assumptions, then he argues against (3), then he discusses locality and realism, and only then he mentions superdeterminism, retro-temporal causation, just to discard them immediately.)

@joigus: as you see, Zeilinger argues against superdeterminism. He treats it as a kind of 'last straw'. This is his argument:

Quote

Just for completeness, let us mention that some other positions are also possible, at least in principle.  One is the  assumption of total determinism.  In that case, everything is predetermined, including the decision of the observer about what he wants to measure. Thus, the question of what property the particle would carry if he were to measure something else would not come up at all, and therefore, the logical line of reasoning that led to Bell’s inequality could not be carried out. It is obvious that such a position would completely pull the rug out from underneath science. What would it mean to  do an experiment if that were the case? After all, an experiment is asking nature a question. If nature itself determines  the question, then we might as well not ask that question at all.

For completeness the 5th:

Quote

Another logically possible position would be to assume that the individual measurements of the individual particles act back into the past. From that point of view, they would influence the source and tell the source, back in the past, with which properties to emit each particle. It is again obvious that such a position would mean a very radical rewriting of our views of space and time.

Hi Studiot!

Does that mean the left and right side of the brain are entangled?

Ok, back to business: I found a pdf of Zeilinger's book. This is the paragraph immediately after the paragraph @bangstromcited:

Quote

The other possibility would be for us to give up the picture of a world that exists in all its properties independent of us. That would mean that we have a very essential influence on reality just by deciding which measurement to perform.There are indeed hints that this might be the message we have to accept. The most significant result in that connection is the so-called Kochen-Specker paradox.It would go too far to explain it in detail here. A brief mention of the result must suffice. The Kochen-Specker paradox can be stated rather easily. It says that even for individual quantum systems, if they are sufficiently complex, it is not possible to assign to them elements of reality that explain all possible experimental results independent of the full experimental context, i.e. which measurement is performed at the same time on the same system. Now, since Kochen and Specker only considered measurements on single quantum particles, the locality hypothesis does not come into play.

From a Dutch newspaper:

6 hours ago, bangstrom said:

" Nearly all physicists agree that the experiments have shown that local realism is an untenable position. The viewpoint of most physicists is that the violation of Bell's inequality shows us that quantum mechanics is nonlocal. This nonlocality is exactly what Albert Einstein called "spooky"; it seems eerie that the act of measuring one particle could instantly influence the other one." From "Dance of the Photons" p. 286

This is not fair. You should have included the next paragraph, where Zeilinger gives his own viewpoint. It fits pretty well to @joigus post. Pity enough I only have the the original German version, and translating from one foreign language to another one is a bit difficult. But in my summary: he carefully proposes that letting go realism is the better solution, and refers to the Kochen-Specker theorem, which leads to a similar solution, even without entanglement. Maybe you could cite this paragraph here too? Until now I could not find the text somewhere on the internet.

So now, I can add Zeilinger to my list, but only half-half, because he does not express himself as strong as the others on the list. But his tendency is clear.

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.

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.🤪

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:

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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:

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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

1. QM does not allow for FTL causation. Watch my wording: causation. So no signal, (inter)action, affect, or whatever.
2. The conclusion of Bell's theorem is: no local hidden classical system can reproduce the correlations predicted by QM.
3. 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.

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...

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.

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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...