Does in EPR problem transfer anything between two particle?

[efaizi]

Does in EPR problem transfer anything between two particle? If it transfer, then it violates principle of special relativity. Is this statement true?
Thanks

 

[yuiop]

Does in EPR problem transfer anything between two particle? If it transfer, then it violates principle of special relativity. Is this statement true?
Thanks

The violation of Bell's inequalities in EPR type experiments implies that the results can not be explained by a theory that is both local and realistic. A local theory is one that only allows particles access to information in the past light cone, i.e. information can only be transferred at the speed of light. If we insist on holding onto locality then we need an "unrealistic" (non-classical) theory to explain what is happening. One such unrealistic theory is the Many Worlds Interpretation that does not require communications at greater than the speed of light so the existence of unrealistic theories like the MWI means that EPR type experiments do not conclusively prove superluminal communications because there are alternative explanations. However, if we explain what happens in the EPR experiments by non-local interactions, it does not (IMHO) violate the principle of special relativity. It can be shown that if we have two macroscopic observers, that they can not pass information to each other at greater than the speed of light using an EPR type set up. Any apparent superluminal communication between microscopic entangled particles (which can only be confirmed at a later time) does not translate to superluminal communications at the macroscopic level. This means special relativity is valid for macroscopic systems.

 

[DrChinese]

Just to add to the above: it is *possible* that effects can flow from the future to the past. In such case, it would be possible to maintain Special Relativity within a quantum interpretation. There are other interpretations in which SR is maintained as well.

And of course there is no useful information transfer in EPR type experiments.

 

[eaglelake]

Does in EPR problem transfer anything between two particle? If it transfer, then it violates principle of special relativity. Is this statement true?
Thanks

The difficulty here is that we assume that the two particles are different and independent of each other. Bohr told us many years ago that they are inseparable: they are a single entity. This is hard to imagine since they are spatially separated. Nevertheless, in quantum mechanics they are one! In fact, the entire apparatus including the particles and measuring devices make up a whole that has no classical analog. The error is to treat each particle as a classical object, with its own trajectory and its own energy, momentum, position, etc. Such thinking leads to much confusion and misconceptions.
To answer your question: If there was some kind of a interaction between the particles, then yes, special relativity would be violated. But there is no interaction between the particles. They are not classical particles and they do not behave that way.

 

[DrChinese]

The difficulty here is that we assume that the two particles are different and independent of each other. Bohr told us many years ago that they are inseparable: they are a single entity. This is hard to imagine since they are spatially separated. Nevertheless, in quantum mechanics they are one! In fact, the entire apparatus including the particles and measuring devices make up a whole that has no classical analog. The error is to treat each particle as a classical object, with its own trajectory and its own energy, momentum, position, etc. Such thinking leads to much confusion and misconceptions.
To answer your question: If there was some kind of a interaction between the particles, then yes, special relativity would be violated. But there is no interaction between the particles. They are not classical particles and they do not behave that way.

Well said!

 

[efaizi]

To answer your question: If there was some kind of a interaction between the particles, then yes, special relativity would be violated. But there is no interaction between the particles. They are not classical particles and they do not behave that way.[/QUOTE]

Is there any proof for this claim? If there is please guide me.

 

[harrylin]

Just to add to the above: it is *possible* that effects can flow from the future to the past. In such case, it would be possible to maintain Special Relativity within a quantum interpretation. [..].

That is impossible by definition, IMHO.
According to who (or what theory) is it possible?

Besides, quantum mechanics has, just like special relativity, different interpretations.
Thus, what do you mean with "a quantum interpretation"?

 

[DrChinese]

That is impossible by definition, IMHO.
According to who (or what theory) is it possible?

Besides, quantum mechanics has, just like special relativity, different interpretations.
Thus, what do you mean with "a quantum interpretation"?

There are several retrocausal (future influences past) interpretations of QM. They go by different names and have somewhat different foundational premises. But the main idea is that time is essentially symmetric at the quantum level.

 

[eaglelake]

To answer your question: If there was some kind of a interaction between the particles, then yes, special relativity would be violated. But there is no interaction between the particles. They are not classical particles and they do not behave that way.

Is there any proof for this claim? If there is please guide me.[/QUOTE]

EPR and Bell-like experiments assume separability and they all give erroneous results. The physics literature is full of such real experiments. Separability is a classical characteristic, but not a quantum one. Further, no interaction has ever been found that links the two particles. An interaction implies the application of forces and the exchange of energy and momentum. We are good at measuring such things and, yet, no one has ever been able to observe it.

Bell's inequality test: more ideal than ever - Aspect is a good place to start.

Best wishes

 

[harrylin]

EPR and Bell-like experiments assume separability and they all give erroneous results. The physics literature is full of such real experiments. Separability is a classical characteristic, but not a quantum one. Further, no interaction has ever been found that links the two particles. An interaction implies the application of forces and the exchange of energy and momentum. We are good at measuring such things and, yet, no one has ever been able to observe it.

Bell's inequality test: more ideal than ever - Aspect is a good place to start.

Best wishes

For an alternative opinion see for example De Raedt, as discussed in this thread:
https://www.physicsforums.com/showthread.php?t=369286&page=4

 

[QuantumClue]

Just to add to the above: it is *possible* that effects can flow from the future to the past. In such case, it would be possible to maintain Special Relativity within a quantum interpretation. There are other interpretations in which SR is maintained as well.

And of course there is no useful information transfer in EPR type experiments.

Like Cramers transactional interpretation?

Dr Chinese, I think it be wise to note that if you are willing to believe that effects can flow retrocausally, this also requires offer wave moving in the time direction we are most attuned with. You cannot have echo waves without offer waves, and then expect a transaction to occur. It almost a matter of relativity when concerning echo waves. $$F_1 = exp^{i(kr- \omega t)}$$ for $$t>T_1$$ and an advanced plane wave comes in the form $$G_1 = exp^{-i(kr- \omega t)}$$ for $$t<T_1$$.

However, physical waves are not tranferred between two physical systems. In this case, information would be very much ethereal... you might as well resort to some kind of hidden variable theory, or resort to some kind of superdeterminism.

 

[DrChinese]

For an alternative opinion see for example De Raedt, as discussed in this thread:
https://www.physicsforums.com/showthread.php?t=369286&page=4

Not sure what the De Raedt simulations have to do with this thread. I would not push that as an alternative QM interpretation as this is not generally accepted as equivalent to QM. In fact, Bell shows it cannot be.

 

[harrylin]

Not sure what the De Raedt simulations have to do with this thread. I would not push that as an alternative QM interpretation as this is not generally accepted as equivalent to QM. In fact, Bell shows it cannot be.

I thought that you had studied their papers?! :uhh:
As a matter of fact, it has everything to do with this thread, if they are right then no "spooky", "superluminal" action takes place.
I was as much convinced by Bell's inequality as by David Copperfield's tricks - or spooks.
Now De Raedt appears to disproof Bell, both in theory and by means of counter examples. And it's not just about simulations but about probability calculations. Thus, please continue the discussion in that thread!

 

[DrChinese]

I thought that you had studied their papers?! :uhh:
As a matter of fact, it has everything to do with this thread, if they are right then no "spooky", "superluminal" action takes place.
I was as much convinced by Bell's inequality as by David Copperfield's tricks - or spooks.
Now De Raedt appears to disproof Bell, both in theory and by means of counter examples. And it's not just about simulations but about probability calculations. Thus, please continue the discussion in that thread!

That thread is a place to discuss, not this one. The concepts of De Raedt are quite complex and if you want to discuss somewhere else I will. It does not overturn Bell, nor does it really agree with QM. It exploits the fair sampling loophole, which has already been closed anyway (although there is some dispute on this point).

I have studied their simulation and am still analyzing some of the elements of their mechanism. They have kindly worked with me to understand the computer portion of their ideas.

 

[harrylin]

That thread is a place to discuss, not this one. The concepts of De Raedt are quite complex and if you want to discuss somewhere else I will. It does not overturn Bell, nor does it really agree with QM. [..]

Eaglelake's claim that "EPR and Bell-like experiments assume separability and they all give erroneous results" is met with a contrary claim in the recent literature, and I referred to the discussion in the other thread for details. I will keep an eye open for how the discussion there progresses.

 

[DrChinese]

Eaglelake's claim that "EPR and Bell-like experiments assume separability and they all give erroneous results" is met with a contrary claim in the recent literature, ...

It is generally accepted that the EPR conclusion (regarding the simultaneous reality of non-commuting observables) is incorrect. There are no - and I do mean zero - recent experiments which cast any doubt on the main Bell-Aspect result: QM is correct and Einstein was wrong on this point. On the other hand, there remain - and always will remain - a small and stubborn group of doubters who will refuse to accept the experimental literature as definitive. Are you one of those?

 

[harrylin]

DrChinese wrote: "there [..] always will remain a small and stubborn group of doubters who will refuse to accept the experimental literature as definitive." [+ apparent violation of forum rules].

IMHO, while we must value abundant experimental data, it would be unscientific to consider existing interpretations of subtle issues to be "definitive". Thus your question makes me wonder. :uhh:
However, there is no issue with the experimental literature involved here (at least, not that I know of)... thus your question makes me wonder even more!

No doubt, there will always be stubborn disbelievers who refuse to accept overwhelming experimental evidence; while on the other hand, there will also always be stubborn, dogmatic people who refuse to reconsider their opinion when new insights are published.

It's essential for science to always keep a critical and open mind.

Best regards,
Harald

 

[harrylin]

Intersting facial animations aside (how DO you make those?) I'm not hearing any substance in your post, other than accusations. Are YOU arguing for the Fair Sampling Loophole, which I'd say is approaching complete rejection, is something you're arguing for? A critical and open mind doesn't cling to old notions once they've been thoroughly discredited to the satisfaction of all but a vocal minority.

If you use physicsforums.com (is there another way?), you will find the facial expressions next to Fonts. I carefully tried to avoid to reply with personal accusations to an apparent personal accusation by drChinese. Phrases that appear to be an attempt to "put down" another member are specifically forbidden on this forum!

I do not understand your logic, are you arguing for spookiness? A critical and open scientific mind will value a critical statistical assessments of extraordinary claims. A recent thread is about a publication according to which ESP has been proven: there it was argued that extraordinary claims require extraordinary evidence, and also there another publication was found with a critical statistical analysis that seems to invalidate the extraordinary claims.
Thus I am looking with much interest how this plays out in the peer reviewed literature.

PS: De Raedt and co-authors "do not invoke detector inefficiencies or anything related to fair sampling." http://iopscience.iop.org/0295-5075/87/6/60007
Please don't shoot the messenger!

 

[harrylin]

I'm arguing for Non-Locality, but if you want to call it spookiness, then yeah. I'm not arguing for information to exceed c however, just non-locality. You're arguing for what, the Bohmian view? "SuperDetermininsm aka god"? You can't be arguing for Local Hidden Variables, unless you just think QM is junk, so I'm a bit puzzled by your approach. [..]

I'm not arguing for anything - just a curious onlooker! But I'm slowly making myself familiar with the issues and arguments. As a result, I was thinking non-locality too until recently.

Now a few recent publications such as the one from which I cited claim* that local hidden variables can exist together with QM - in agreement with EPR (and in disagreement with Bell). That would of course be the most common-sense solution, if it's correct. And then, obviously, nothing superluminal is supposed to happen either.

*a phrase from their conclusion: "neither realism nor Einstein locality need be abandoned because of a violation of Bell’s inequalities."

 

[DrChinese]

...while on the other hand, there will also always be stubborn, dogmatic people who refuse to reconsider their opinion when new insights are published...

There haven't been any new experimental results. So there is really nothing to consider.

There are lots of "disproofs" of Bell/Aspect, and I review a lot of them. Here are some of the diehards who are publishing these:

Santos, Hess, Philipp, Broda, Christian, Zhao, Kracklauer, Laudisa, Nieuwnehuizen.

So obviously these folks have failed to make a persuasive argument, as none of their attacks are any more scientifically accepted than those of De Raedt et al. I won't bother to fend these off, you are free to believe whatever you like. Just don't use this forum as a place to post non-standard science as that violates forum rules. You should do that on your own web site.

 

[DrChinese]

I have had private discussions with Drs. De Raedt and Michielsen. They are very dedicated, and are working systematically towards a specific goal - and making interesting progress, I might add. It is a very impressive computer model indeed, and I am still studying how it works (my profession is programming). However, they have not yet achieved the point at which they have a completely suitable model, and that is not just my conclusion. But it is very complicated to discuss and debate unless you are very familiar with the intricate details of theory. Otherwise, it just evolves into a debate over claims. On this site, accepted scientific theory wins as this is not a site to debate novel research.

My recommendation is to study EPR, Bell and Aspect. You seem to have done a fair bit of that. Next, follow the work of Zeilinger et al, Gisin et al, and their many esteemed coworkers so you understand what is going on in the experimental and theoretical areas of entanglement. I can tell you where to look if that helps, start in arxiv. Their work essentially makes the entire De Raedt et al program meaningless in the sense that if you accept local realism, you won't even agree that quantum entanglement exists. And yet the experimental record shows it to exist time and time again. On the other hand, it is the ultimate quest of De Raedt et al to come up with an experiment that can demonstrate their ideas. So far, that has not happened - but if they do, great.

 

[harrylin]

[..]
There are lots of "disproofs" of Bell/Aspect, and I review a lot of them. Here are some of the diehards who are publishing these:

Santos, Hess, Philipp, Broda, Christian, Zhao, Kracklauer, Laudisa, Nieuwnehuizen.

So obviously these folks have failed to make a persuasive argument, as none of their attacks are any more scientifically accepted than those of De Raedt et al. I won't bother to fend these off, you are free to believe whatever you like. Just don't use this forum as a place to post non-standard science as that violates forum rules. You should do that on your own web site.

Funny enough, you objected to my referral here to the thread on DeRaedt which, as it happens, was started by... you!
Indeed, discussions like the one you started about new views that are proposed in professional peer-reviewed journals are perfectly fitting for this forum:

There are many open questions in physics, and we welcome discussion on those subjects provided the discussion remains intellectually sound. It is against our Posting Guidelines to discuss, in most of the PF forums or in blogs, new or non-mainstream theories or ideas that have not been published in professional peer-reviewed journals or are not part of current professional mainstream scientific discussion.

 

[efaizi]

So far, I didn't have understand that is EPR problem violate SR or not?

 

[harrylin]

So far, I didn't have understand that is EPR problem violate SR or not?

Perhaps you mean, if QM violates SR?

Philosophically: that depends on opinion and interpretation! *
Technically: no. QM does not require that anything measurable propagates faster than light.

* Whole books have been written about that question. I read (and liked) Tim Maudlin, "Quantum Non-locality and Relativity".

 

[thenewmans]

So far, I didn't have understand that is EPR problem violate SR or not?

There are some parts of QM for which nobody has been able to design an experiment. In QM, these untestable theories are usually called interpretations. They’re kind of philosophical. Some of these interpretations include some instantaneous results. So they conflict with SR, but only at a certain level. Since interpretations are untestable, there’s no test you can do to demonstrate a conflict between QM and SR. So usually physicists say that the 2 theories are in agreement.

Now let’s cover the EPR paradox, which was intended to show that QM is incomplete and some hidden variable was needed in order for QM to avoid breaking some established principal. 30 years later, Bell shows that no hidden variable could possibly explain the results predicted by QM. The experiments were performed and, sure enough, QM is correct. Some interpret that as QM conflicting with SR. That’s not necessarily the case. So that still leaves us with the issue of which established principal QM must break. It usually comes down to either locality or realism. This is where all those interpretations come in.

 

[DrChinese]

There are many open questions in physics, and we welcome discussion on those subjects provided the discussion remains intellectually sound. It is against our Posting Guidelines to discuss, in most of the PF forums or in blogs, new or non-mainstream theories or ideas that have not been published in professional peer-reviewed journals or are not part of current professional mainstream scientific discussion.

After a few thousand posts, I think the moderators know I advocate mainstream science. And sometimes there is discussion where the main idea of the thread gets hijacked. That is essentially what you are doing. So occasionally I open a separate thread to allow the original thread to remain on topic. Let's take further discussion of De Raedt elsewhere.

The fact is, there is a generally accepted idea called "quantum non-locality". That idea does not violate special relativity in the sense that superluminal signals are possible. I think that pretty well wraps things up here.

 

[DrChinese]

So far, I didn't have understand that is EPR problem violate SR or not?

EPR was simply mistaken in their final conclusion.

There are no tenets of QM which violate any tenets of SR. The concept of quantum non-locality is used to describe/label the fact that entangled systems are not localized in spacetime. In fact, it is questionable as to whether any quantum object can be considered localized in spacetime.

 

[harrylin]

After a few thousand posts, I think the moderators know I advocate mainstream science. And sometimes there is discussion where the main idea of the thread gets hijacked. That is essentially what you are doing. So occasionally I open a separate thread to allow the original thread to remain on topic. Let's take further discussion of De Raedt elsewhere.

The fact is, there is a generally accepted idea called "quantum non-locality". That idea does not violate special relativity in the sense that superluminal signals are possible. I think that pretty well wraps things up here.

The pot calling the kettle black? If you want to challenge De Raedt's paper on Boole and Bell, yes please start a thread about it!

And indeed QM and SR are not in conflict: neither postulates "what really happens" and their predictions can be blended. However, I think that your wrapping up is a bit too hasty.

Maudlin explains rather well in his book how mainstream quantum physics conflicts with mainstream relativity. Mainstream relativists hold, as Maudlin put it, that no influence can travel faster than light, while mainstream quantum physicists hold that the quantum connection is instantaneous (over whatever distance).

Indeed, most relativists insist on locality, rejecting the existence of an absolute frame. And now that quantum physicists claim that their experiments of the last decades prove them right, most relativists seem to be unwilling to discuss this topic.

Harald