Some observations/questions about the Delft Experiment

Foundations of physics and/or philosophy of physics, and in particular, posts on unresolved or controversial issues

Re: Some observations/questions about the Delft Experiment

Postby Joy Christian » Thu Oct 24, 2019 1:42 pm

minkwe wrote:
... I dare say "fraud" has not been ruled out.

Wow!

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Re: Some observations/questions about the Delft Experiment

Postby minkwe » Thu Oct 24, 2019 2:29 pm

Joy Christian wrote:
minkwe wrote:... I dare say "fraud" has not been ruled out.

Wow!

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minkwe wrote:Perhaps you are hinting at the question of how the data came to be. And that is an wide open question, and though I'm not making any suggestion here, I dare say "fraud" has not been ruled out.


Please don't get me wrong. I have no evidence of fraud by anyone here, all I'm saying is there are many mechanisms by which certain data came to exist and fraud is one possibility. Perhaps others have ruled out fraud, but not having the raw data, I have no evidence one way or the other.
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Re: Some observations/questions about the Delft Experiment

Postby local » Thu Oct 24, 2019 3:17 pm

It's perfectly acceptable to suggest that there is hanky-panky when the authors hide their data. Hensen et al could so easily remove any doubts in this regard by releasing the full raw data. The fact that they don't do that is very telling. I am quite willing to cry foul. Data fabrication by selective postprocessing at this point has the highest prior probability. Ancel Keys performed similar jiggery-pokery with his cholesterol study (excluding nations whose data did not fit his hypothesis), which sadly led to the ruination of the health of millions, and to the current world-wide type 2 diabetes and obesity epidemics.

Here are the excuses offered to me so far by our intrepid interlocutor Gill:

1. The dataset is too big.
2. You are an unreliable researcher.
3. You don't deserve the data because you make "aggressive" posts.

It's despicable, like something out of Monty Python. And those guys think they deserve a Nobel Prize? :roll:
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Re: Some observations/questions about the Delft Experiment

Postby localyokel » Thu Oct 24, 2019 6:16 pm

Are you suggesting they are concealing data, that is that they have gone ahead and hidden variables, that when analyzed would prove the existence of hidden variables?
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Re: Some observations/questions about the Delft Experiment

Postby FrediFizzx » Thu Oct 24, 2019 6:22 pm

localyokel wrote:Are you suggesting they are concealing data, that is that they have gone ahead and hidden variables, that when analyzed would prove the existence of hidden variables?

I think that local thinks they are in fact concealing data which it seems like they might be. But not for the reasons you are suggesting. Personally, I have no reason to suspect foul play as particle physics validates quantum theory very sufficiently.
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Re: Some observations/questions about the Delft Experiment

Postby gill1109 » Thu Oct 24, 2019 6:30 pm

There is no "post-selection" in the Hensen et al. experiment. There is something you might call "pre-selection". It does not constitute a "loophole".

It is a three-party Bell-type experiment. There are three locations: let's call them the labs of Alice, Bob and Caspar. An electron spin in a Nitrogen-Vacancy defect in a diamond crystal is repeatedly excited by a laser in both Alice's and Bob's laboratories. Occasionally, both spins emit a photon which occasionally, both are detected on the other side of a birefringent polarizing beam splitter in Casper's lab, where there are two photo-detectors. Occasionally, both of those detectors click. If so, one doesn't know which photon went which way. On those occasions, according to conventional QM, Alice and Bob's two spins were entangled during a small time interval, during which also the two spins rapidly got measured in randomly chosen directions.

All the time, random settings are being chosen in Alice and Bob's labs, the spins of the two electrons in the NV defects are being measured, the settings and outcomes are registered, the spins are "reset" and then excited again.

The experimenters are interested in the correlations between Alice and Bob's outcomes, given Alice and Bob's settings, and given Casper's two detections.

There is no direct point in keeping hold of all the data which Alice and Bob temporarily had in their possession on the occasions when Caspar did not get two clicks. You can read in the original papers what was the thinking here and what happened to it. It no longer exists. Crying fraud and demanding to see it suggests to me that you didn't actually take much notice of the published description of the experiment.

If the scientists of the world think it is important, they had better get the taxpayers of the world to fund a new experiment. As I said before, it would be smart to have the new experiment performed by different research groups in different places, and while they are at it, to run the experiment for about 10 times as long, so as, hopefully, to get a five sigma deviation from the predictions of local realism, which is what one can predict, assuming that the true value of S was indeed, as QM theory predicts, and the data certainly suggests, about 2.4 (the data gives this measured parameter a standard deviation of about 0.2). That's a value about halfway between the LR bound of 2 and the QM bound of 2.828...

As Fred says, the results of the Delft experiment fit perfectly well to what quantum mechanics predicts, there is no need whatever to suspect any kind of fraud. It is however true that the size of the experiment is much too small to have had much chance of detecting the opposite (any departure from QM).

I haven't seen Joy Christian's specific modelling of this particular three-party Bell experiment, nor how his theory should be extended or adapted to deal with observed conditional correlations between Alice and Bob's outcomes, conditional on Alice's, Bob's and Caspar's settings and Caspar's outcomes. As I understand his writings, he argues that it is un-physical to compare one correlation to three others, each of the four measured on data collected in distinct sub-experiments. But he happily himself derives the Tsirelson bound of 2 sqrt 2 and the no-signalling bound of 4. Fred also confirms that the no-signalling bound of 4 is a valid bound. Fred and Joy claim that their data-rejection simulations can be set to illustrate that all three bounds (2, 2 sqrt 2, and 4) can be achieved in appropriate circumstances. So I don't understand the remarks that experimenters "used the wrong inequality" since "you can't violate a mathematical inequality" anyway. Obviously, no-one is going to get the Nobel prize, nor the Abel prize if they are young enough, for showing that if you have four numbers between +/-1, then the sum of three of them minus the fourth can't exceed 4.

The so-called "no-signalling" bound (which could be attained by so-called Popescu-Rohrlich boxes if they existed) is rather trivial in this case. The principle of "information causality" introduced by Marcin Pawlowski and his collaborators a few years ago shows that the Tsirelson bound of 2 sqrt 2, which follows from assuming validity of QM (but not necessarily two dimensional quantum systems and perfect spin measurements), shows that the 2 sqrt 2 bound follows from general causality principles which intuitively should hold even if QM is not true, i.e., the principles should hold, and hence the bound be true, in much greater universality in reasonable physical theories "beyond QM".
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Re: Some observations/questions about the Delft Experiment

Postby gill1109 » Thu Oct 24, 2019 6:37 pm

gill1109 wrote:There is no "post-selection" in the Hensen et al. experiment. There is something you might call "pre-selection". It does not constitute a "loophole".

It is a three-party Bell-type experiment. There are three locations: let's call them the labs of Alice, Bob and Caspar. An electron spin in a Nitrogen-Vacancy defect in a diamond crystal is repeatedly excited by a laser in both Alice's and Bob's laboratories. Occasionally, both spins emit a photon which occasionally, both are detected on the other side of a birefringent polarizing beam splitter in Casper's lab, where there are two photo-detectors. Occasionally, both of those detectors click. If so, one doesn't know which photon went which way. On those occasions, according to conventional QM, Alice and Bob's two spins were entangled during a small time interval, during which also the two spins rapidly got measured in randomly chosen directions.

All the time, random settings are being chosen in Alice and Bob's labs, the spins of the two electrons in the NV defects are being measured, the settings and outcomes are registered, the spins are "reset" and then excited again.

The experimenters are interested in the correlations between Alice and Bob's outcomes, given Alice and Bob's settings, and given Casper's two detections.

There is no direct point in keeping hold of all the data which Alice and Bob temporarily had in their possession on the occasions when Caspar did not get two clicks. You can read in the original papers what was the thinking here and what happened to it. It no longer exists. Crying fraud and demanding to see it suggests to me that you didn't actually take much notice of the published description of the experiment.

If the scientists of the world think it is important, they had better get the taxpayers of the world to fund a new experiment. As I said before, it would be smart to have the new experiment performed by different research groups in different places, and while they are at it, to run the experiment for about 10 times as long, so as, hopefully, to get a five sigma deviation from the predictions of local realism, which is what one can predict, assuming that the true value of S was indeed, as QM theory predicts, and the data certainly suggests, about 2.4 (the data gives this measured parameter a standard deviation of about 0.2). That's a value about halfway between the LR bound of 2 and the QM bound of 2.828...

As Fred says, the results of the Delft experiment fit perfectly well to what quantum mechanics predicts, there is no need whatever to suspect any kind of fraud. It is however true that the size of the experiment is much too small to have had much chance of detecting the opposite (any departure from QM).

I haven't seen Joy Christian's specific modelling of this particular three-party Bell experiment, nor how his theory should be extended or adapted to deal with observed conditional correlations between Alice and Bob's outcomes, conditional on Alice's, Bob's and Caspar's settings and Caspar's outcomes. As I understand his writings, he argues that it is un-physical to compare one correlation to three others, each of the four measured on data collected in distinct sub-experiments. But he happily himself derives the Tsirelson bound of 2 sqrt 2 and the no-signalling bound of 4. Fred also confirms that the no-signalling bound of 4 is a valid bound. Fred and Joy claim that their data-rejection simulations can be set to illustrate that all three bounds (2, 2 sqrt 2, and 4) can be achieved in appropriate circumstances. So I don't understand the remarks that experimenters "used the wrong inequality" since "you can't violate a mathematical inequality" anyway. Obviously, no-one is going to get the Nobel prize, nor the Abel prize if they are young enough, for showing that if you have four numbers between +/-1, then the sum of three of them minus the fourth can't exceed 4.

The so-called "no-signalling" bound (which could be attained by so-called Popescu-Rohrlich boxes if they existed) is rather trivial in this case. The principle of "information causality" introduced by Marcin Pawlowski and his collaborators a few years ago shows that the Tsirelson bound of 2 sqrt 2, which follows from assuming validity of QM (but not necessarily two dimensional quantum systems and perfect spin measurements), shows that the 2 sqrt 2 bound follows from general causality principles which intuitively should hold even if QM is not true, i.e., the principles should hold, and hence the bound be true, in much greater universality in reasonable physical theories "beyond QM".


Gossip about Nobel prizes is just ... gossip. People can spread fake news, and try to influence whatever discussion is actually going on. Here is my five cents worth. We know that John Bell would likely have been nominated for the Nobel prize just before he died of a sudden and completely unexpected brain haemorrhage at age 62. The "loophole-free" experiments of 2015, three published in 2015 and one in 2016, seem to many people to collectively form a big milestone for science. In the meantime they even got confirmed by yet bigger and better experiments (Pan and Zeilinger in China; Acin and Gisin in Barcelona; ...). Certainly a much bigger milestone than the recent quantum supremacy claims at Google and IBM, which should not be taken seriously; the term "quantum supremacy" has got so devalued in a few years that it ought to be banned. And it already had a politically incorrect flavour to it. In short, it's a joke, and probably a joke in poor taste.

There is no quantum computer in sight. But there does seem to be a quantum internet on the not-distant horizon. Will the Netherlands, or will China, get there first? Or are there dark horses in the race, too?
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Re: Some observations/questions about the Delft Experiment

Postby local » Thu Oct 24, 2019 7:26 pm

gill1109 wrote: It no longer exists.

It's stunning that Gill now so calmly acknowledges that nobody will ever be able to see the data to independently analyze the Delft (Hensen et al) experiment. Dog ate the homework! The Nobel committee will not be amused. Hensen et al are unable to disprove the hypothesis that they manipulated the data to produce only an artifactual violation. They ask us to trust them. :lol:

Let's be crystal clear. Gill informs us portions of the data were selectively destroyed. I claim that this destruction was biased to produce only an artifactual violation.

Ancel Keys would be proud.
Last edited by local on Thu Oct 24, 2019 9:24 pm, edited 1 time in total.
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Re: Some observations/questions about the Delft Experiment

Postby gill1109 » Thu Oct 24, 2019 9:12 pm

local wrote:
gill1109 wrote: It no longer exists.

It's stunning that Gill now so calmly acknowledges that nobody will ever be able to see the data to independently analyze the Delft (Hensen et al) experiment, after reassuring us he would get it from his friends. Dog ate the homework! The Nobel committee will not be amused. Hensen et al are unable to disprove the hypothesis that they manipulated the data to produce only an artifactual violation. They ask us to trust them. :lol:

Let's be crystal clear. Gill informs us portions of the data were selectively destroyed. I claim that this destruction was intentionally biased to produce only an artifactual violation.

Ancel Keys would be proud.

Let's be crystal clear. You have no evidence whatsoever on which to base your disgusting accusation. Dog ate homework and threw up on the carpet. Yech...
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Re: Some observations/questions about the Delft Experiment

Postby local » Thu Oct 24, 2019 9:36 pm

1. The dataset is too big.
2. You are an unreliable researcher.
3. You don't deserve the data because you make "aggressive" posts.
4. My dog ate the data.
5. You are disgusting.
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Re: Some observations/questions about the Delft Experiment

Postby FrediFizzx » Thu Oct 24, 2019 9:39 pm

Ok, enough of that. I'm going to start deleting posts like that.
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Re: Some observations/questions about the Delft Experiment

Postby localyokel » Fri Oct 25, 2019 6:00 am

gill1109 wrote:There is no "post-selection" in the Hensen et al. experiment. There is something you might call "pre-selection". It does not constitute a "loophole".

It is a three-party Bell-type experiment. There are three locations: let's call them the labs of Alice, Bob and Caspar. An electron spin in a Nitrogen-Vacancy defect in a diamond crystal is repeatedly excited by a laser in both Alice's and Bob's laboratories. Occasionally, both spins emit a photon which occasionally, both are detected on the other side of a birefringent polarizing beam splitter in Casper's lab, where there are two photo-detectors. Occasionally, both of those detectors click. If so, one doesn't know which photon went which way. On those occasions, according to conventional QM, Alice and Bob's two spins were entangled during a small time interval, during which also the two spins rapidly got measured in randomly chosen directions.

All the time, random settings are being chosen in Alice and Bob's labs, the spins of the two electrons in the NV defects are being measured, the settings and outcomes are registered, the spins are "reset" and then excited again.

The experimenters are interested in the correlations between Alice and Bob's outcomes, given Alice and Bob's settings, and given Casper's two detections.

There is no direct point in keeping hold of all the data which Alice and Bob temporarily had in their possession on the occasions when Caspar did not get two clicks. You can read in the original papers what was the thinking here and what happened to it. It no longer exists. Crying fraud and demanding to see it suggests to me that you didn't actually take much notice of the published description of the experiment.

If the scientists of the world think it is important, they had better get the taxpayers of the world to fund a new experiment. As I said before, it would be smart to have the new experiment performed by different research groups in different places, and while they are at it, to run the experiment for about 10 times as long, so as, hopefully, to get a five sigma deviation from the predictions of local realism, which is what one can predict, assuming that the true value of S was indeed, as QM theory predicts, and the data certainly suggests, about 2.4 (the data gives this measured parameter a standard deviation of about 0.2). That's a value about halfway between the LR bound of 2 and the QM bound of 2.828...

As Fred says, the results of the Delft experiment fit perfectly well to what quantum mechanics predicts, there is no need whatever to suspect any kind of fraud. It is however true that the size of the experiment is much too small to have had much chance of detecting the opposite (any departure from QM).

I haven't seen Joy Christian's specific modelling of this particular three-party Bell experiment, nor how his theory should be extended or adapted to deal with observed conditional correlations between Alice and Bob's outcomes, conditional on Alice's, Bob's and Caspar's settings and Caspar's outcomes. As I understand his writings, he argues that it is un-physical to compare one correlation to three others, each of the four measured on data collected in distinct sub-experiments. But he happily himself derives the Tsirelson bound of 2 sqrt 2 and the no-signalling bound of 4. Fred also confirms that the no-signalling bound of 4 is a valid bound. Fred and Joy claim that their data-rejection simulations can be set to illustrate that all three bounds (2, 2 sqrt 2, and 4) can be achieved in appropriate circumstances. So I don't understand the remarks that experimenters "used the wrong inequality" since "you can't violate a mathematical inequality" anyway. Obviously, no-one is going to get the Nobel prize, nor the Abel prize if they are young enough, for showing that if you have four numbers between +/-1, then the sum of three of them minus the fourth can't exceed 4.

The so-called "no-signalling" bound (which could be attained by so-called Popescu-Rohrlich boxes if they existed) is rather trivial in this case. The principle of "information causality" introduced by Marcin Pawlowski and his collaborators a few years ago shows that the Tsirelson bound of 2 sqrt 2, which follows from assuming validity of QM (but not necessarily two dimensional quantum systems and perfect spin measurements), shows that the 2 sqrt 2 bound follows from general causality principles which intuitively should hold even if QM is not true, i.e., the principles should hold, and hence the bound be true, in much greater universality in reasonable physical theories "beyond QM".


You've left out why we should expect Alice and Bob's transmissions to Caspar are ever entangled. Why should we ever expect that? If the full data ever is released, and I hold out hope it will be, as it hasn't really been that long since our requests, that answer will help me analyze it.
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Re: Some observations/questions about the Delft Experiment

Postby localyokel » Fri Oct 25, 2019 6:15 am

And the final things you measure are all at the same place at the end, with Caspar? If I have the right picture, and I hope I don't, they made a bunch of assumptions "according to quantum theory", and some of those imply it doesn't matter that it is all local to Caspar at the end. But throw those ASSUMPTIONS out, and since it is all local to Caspar at the end, all sorts of local realist alternatives are easily plausible. All you have proven (actually failed to disprove) if their claims are right, is that their assumptions jibe with the data. But since it is all local to Caspar at the end, it is trivially jibes with a whole host of local realist theories.
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Re: Some observations/questions about the Delft Experiment

Postby minkwe » Fri Oct 25, 2019 7:05 am

gill1109 wrote:There is no "post-selection" in the Hensen et al. experiment. There is something you might call "pre-selection". It does not constitute a "loophole".

This is untrue and can be easily verified even from the data they have released. They released a file "bell_open_data.txt" which contains ~4800 events. The events have been extracted from the raw data, which they did not release. Note that in the experiment you have 3 stations: A, B, C, each of which records data. The file "bell_open_data.txt" contains data which has already been matched and brought together into a single file. How was this done, and how can anyone verify that this was done correctly if the raw data from the individual stations is not available. Secondly, in the paper, they claim that

Hensen et al wrote:Every few hundred milliseconds, the recorded events are transferred
to the PC. During the experiment, about 2 megabyte of data is generated every second. To keep the size of the generated data-set manageable, blocks of about 100000 events are saved to the hard drive only if an entanglement heralding event (E) is present in that block.


The data at A and B are recorded with the following columns (I, S, R0, R1, P, E), while the data at C is recorded with the following columns (S P0, E, P1). They have this data (or had it at one point). Why did they record it if not to use it in one way or another, and why would they destroy it (if claims that the data no longer exists is to be believed).

Note that "bell_open_data.txt" contains 4746 events which corresponds to just ~5% of a single block. And in case you are tempted to think 2 MB a second is large amount of data, let me dispel that notion by informing you that I generate 9 MB of data every 0.1 second for extended periods and transfer large resulting data-sets across the globe on a routine basis.

Finally, they extracted just 245 events from the 4746 events at the analysis stage to demonstrate violation of the inequality.

All of this is called post-selection.
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Re: Some observations/questions about the Delft Experiment

Postby local » Fri Oct 25, 2019 7:41 am

Outstanding post, minkwe, bravo! Your point about the matching is really important.

minkwe wrote:Why did they record it if not to use it in one way or another, and why would they destroy it (if claims that the data no longer exists is to be believed).

I can help you with that. I hypothesize that the unmanipulated full data failed to confirm quantum nonlocality and instead confirmed locality (just as we see for Christensen et al). After all the expense and effort by Hensen et al in pursuit of fame, fortunes, and prizes, they could not abide this terrible failure. So they fiddled the data and then destroyed the original full data so that their malfeasance could never be proven, and so that there would not be an experiment on record disconfirming quantum nonlocality. They didn't want to make the same "mistake" as Christensen et al made, i.e., publishing the full data so researchers could analyze it independently.

I generate 9 MB of data every 0.1 second for extended periods and transfer large resulting data-sets across the globe on a routine basis

And people all over the world regularly download torrent files upwards of 50GB. However, as we have seen, the "data is too large" excuse has already been superceded.
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Re: Some observations/questions about the Delft Experiment

Postby Joy Christian » Fri Oct 25, 2019 7:56 am

local wrote:Outstanding post, minkwe, bravo!

minkwe wrote:Why did they record it if not to use it in one way or another, and why would they destroy it (if claims that the data no longer exists is to be believed).

I can help you with that. I hypothesize that the unmanipulated full data failed to confirm quantum nonlocality and instead confirmed locality (just as we see for Christensen et al). After all the expense and effort by Hensen et al in pursuit of fame, fortunes, and prizes, they could not abide this terrible failure. So they fiddled the data and then destroyed the original full data so that their malfeasance could never be proven, and so that there would not be an experiment on record disconfirming quantum nonlocality. They didn't want to make the same "mistake" as Christensen et al made, i.e., publishing the full data so researchers could analyze it independently.

If ture, then that would certainly qualify to be called "fraud."

In fact, your hypothesis is not an outlier from the historical precedents in science in general or in physics: https://www.amazon.co.uk/Golem-Second-S ... M.+Collins

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Re: Some observations/questions about the Delft Experiment

Postby local » Fri Oct 25, 2019 8:10 am

Joy Christian wrote: If true, then that would certainly qualify to be called "fraud."

Indeed, but it will sadly remain a hypothesis, due to the nefarious actions of Hensen et al.

In fact, your hypothesis is not an outlier from the historical precedents in science in general or in physics: https://www.amazon.co.uk/Golem-Second-S ... M.+Collins

Very interesting link, thank you. And there's Piltdown Man and many others.
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Re: Some observations/questions about the Delft Experiment

Postby localyokel » Fri Oct 25, 2019 8:35 am

I fear my questions above have been forgotten. Can the group answer:
1. Why should we expect Alice and Bob's transmissions to Casper ever get "entangled"?
2. Is it all local to Casper at the end?
In regards to 2:
Richard says "...Casper's lab, where there are two photo-detectors. Occasionally, both of those detectors click. If so, one doesn't know which photon went which way." So I get the impression that Casper does NOT make two measurements that are separated enough from one another to be called nonlocal.

If the answer to 2 is "it is all local to Casper", then I will put my newly printed out copy of Hensen et. al. through the shredder, and seek other data to decide locality vs. nonlocality.
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Re: Some observations/questions about the Delft Experiment

Postby minkwe » Fri Oct 25, 2019 1:42 pm

localyokel wrote:I fear my questions above have been forgotten. Can the group answer:
1. Why should we expect Alice and Bob's transmissions to Casper ever get "entangled"?
2. Is it all local to Casper at the end?
In regards to 2:
Richard says "...Casper's lab, where there are two photo-detectors. Occasionally, both of those detectors click. If so, one doesn't know which photon went which way." So I get the impression that Casper does NOT make two measurements that are separated enough from one another to be called nonlocal.

If the answer to 2 is "it is all local to Casper", then I will put my newly printed out copy of Hensen et. al. through the shredder, and seek other data to decide locality vs. nonlocality.

I wish I understood what you are talking about.
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Re: Some observations/questions about the Delft Experiment

Postby gill1109 » Sat Oct 26, 2019 7:35 am

localyokel wrote:I fear my questions above have been forgotten. Can the group answer:
1. Why should we expect Alice and Bob's transmissions to Casper ever get "entangled"?
2. Is it all local to Casper at the end?
In regards to 2:
Richard says "...Casper's lab, where there are two photo-detectors. Occasionally, both of those detectors click. If so, one doesn't know which photon went which way." So I get the impression that Casper does NOT make two measurements that are separated enough from one another to be called nonlocal.

If the answer to 2 is "it is all local to Casper", then I will put my newly printed out copy of Hensen et. al. through the shredder, and seek other data to decide locality vs. nonlocality.

Answer to question 1. QM tells us this. “Entanglement” is a concept within QM. But you don’t have to believe it. The whole point of the experiment is to investigate what happens under the assumption of local realism.

Answer to question 2. Casper’s measurements are very close together in time and space. They constitute one measurement with four possible outcomes.

There are three parties. Alice and Bob have binary inputs and binary outputs, Caspar’s has zero inputs and one quaternary output.But in fact three of the four are grouped, it can also be considered as one binary output,

If you’re not going to read the paper carefully, you had better not have printed it at all in the first place.

Minkwe says it’s postselection. OK call it what you like. Postselection can be harmful. It can be harmless. This is harmless postselection.

Of course if you don’t trust the researchers, don’t bother to read their papers. If you have evidence that they are untrustworthy, publish the evidence.

If your only evidence is “I believe in local realism hence the data must be faked and/or the mathematics wrong” I suggest you just shut up. You harm your own cause by maligning these researchers merely for the purpose of gratifying your own ego. There is something on Wikipedia called “the assumption of good faith”. I think it should also be a working rule when discussing science on a forum where what is written is in public view. Anonymous slander is especially distasteful. It harms the cause of the owner of the forum.
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