Do we need a coincidence counter (for correlation) in delayed erasure?

[San K]

Do we need a coincidence counter (for correlation) in delayed erasure?...in case of repeating the same experiment many times (with one photon at a time) the same way


In the DCQE experiment such as the one listed below

http://grad.physics.sunysb.edu/~amarch/

Notice the polarizer placed before detector Dp. This is used to erase which way information.

Now let's perform the delayed erasure as per the following (same as performed in the link above):
1. We detect S before P
2. Once we have detected S, we place a polarized (eraser) before Dp
3. We repeat this experiment many many times
4. We get an interference pattern, as expected

Now in this case (part of the experiment), do we need the coincidence counter? (for correlating s and p)

I argue we don’t need the coincidence counter because
1. We don’t need to co-relate s and p photons i.e. we don’t’ need to detect the quantum state of the P or S because we are repeating the same sequence of events (i.e. delayed erasure) every time we send a photon pair in a “erased” manner (although delayed)
2. We can remove the “noise” without use of co-incidence counter because we can tell when photon p is expected to arrive at Ds via velocity of light calculations i.e.simply correlate with emission time, however we don’t need to correlated with photon P.

Is the above argument valid? I will then proceed to the next idea/point.

 

[JesseM]

Pretty sure that the total pattern of photons detected at Ds never shows interference no matter what happens at Dp, it's only when you look at subsets of photons at Ds that corresponded to hits at a particular position for Dp that there is any hope of seeing an interference pattern. In general my understanding is that if you have one member of an entangled pair going through a double-slit, then if there is even the potential to measure the second particle in a way that will tell you which slit the first went through, then the total probability distribution for the first particle will never show interference (though there may be an interference pattern in the conditional probability distribution telling you the probability the first particle will be detected at position x given that the second particle was measured to have some property, like that it was detected at a particular position of the Dp detector).

 

[San K]

Pretty sure that the total pattern of photons detected at Ds never shows interference no matter what happens at Dp, it's only when you look at subsets of photons at Ds that corresponded to hits at a particular position for Dp that there is any hope of seeing an interference pattern. In general my understanding is that if you have one member of an entangled pair going through a double-slit, then if there is even the potential to measure the second particle in a way that will tell you which slit the first went through, then the total probability distribution for the first particle will never show interference (though there may be an interference pattern in the conditional probability distribution telling you the probability the first particle will be detected at position x given that the second particle was measured to have some property, like that it was detected at a particular position of the Dp detector).

Jesse, if we just took only those photons who were expected to arrive at times x, y, z at etc at Ds and corresponding to the time they left the BBO...(i.e. if we removed the noise, without correlation in co incidence counter)

would we get any patterns?

Also what you mean by a particular position at Dp?

Keep in mind that in this experiment we are doing erasure every-time, after S strikes and before P is detected. Thus we are simply repeating the same sequence of events.

 

[JesseM]

Jesse, if we just took only those photons who were expected to arrive at times x, y, z at etc at Ds and corresponding to the time they left the BBO...(i.e. if we removed the noise, without correlation in co incidence counter)

would we get any patterns?

I don't think you can ever get interference patterns in Ds without doing a coincidence count with the entangled twins.

Also what you mean by a particular position at Dp?

Look at this diagram:

[PLAIN]http://grad.physics.sunysb.edu/~amarch/PHY5655.gif

Here they show the position of Ds being varied back and forth while the position of Dp is held constant, but I'd imagine you could vary the position of Dp in the same way (or even put multiple detectors in the upper region at once). For any given position of Dp, only a subset of the photons that go to Ds will have twins that go to that position of Dp, right?

 

[San K]

I don't think you can ever get interference patterns in Ds without doing a coincidence count with the entangled twins.

Look at this diagram:

[PLAIN]http://grad.physics.sunysb.edu/~amarch/PHY5655.gif

Here they show the position of Ds being varied back and forth while the position of Dp is held constant, but I'd imagine you could vary the position of Dp in the same way (or even put multiple detectors in the upper region at once). For any given position of Dp, only a subset of the photons that go to Ds will have twins that go to that position of Dp, right?

ya for one thing...i don't understand why they don't simply get a detector with a big screen? that way they don't have to move the detectorsback to my question...i'll try to ask in a more simpler way:

why can we not separate the noise out simply by doing "timing" calculation?

by timing i mean - photon left BBO crystal at 10 am...its expected to arrive at (say) 10:00:0000000001 am...

next photon left BBO crystal at 10:01 am ...its expected to arrive at (say) 10:01:0000000001 am...

the co-incidence counter also tells about the state (+ or - spin or polarization etc) ...however in this case we don't need the co-incidence counter since we are in a predetermined way...putting an eraser every-time...after s strikes and before p strikes

i have a feeling there is something i am missing in the experiment...maybe the polarization of the photons (at the time they strike the detectors) is still needed for some reason...?

 

[unusualname]

You are forgetting about the probabilistic nature of QM. Only ~50% of photons will pass through the polarizer (eraser) and there is no way to know which will and which won't in advance. So you must do a coincidence match to ensure your dataset consists of paired partners which passed through the entire experimental aparatus. (Similarly probabilistic behaviour at wave plates, and of course environmental effects and stray photons which cannot be completely removed even in a pitch dark room)

 

[San K]

You are forgetting about the probabilistic nature of QM. Only ~50% of photons will pass through the polarizer (eraser) and there is no way to know which will and which won't in advance. So you must do a coincidence match to ensure your dataset consists of paired partners which passed through the entire experimental aparatus. (Similarly probabilistic behaviour at wave plates, and of course environmental effects and stray photons which cannot be completely removed even in a pitch dark room)

I think you gave the correct answer.

Why would only 50% pass through the polarizer (eraser)? it is because only the ones that are (say) left handed (or only right handed) polarized will pass?

 

[unusualname]

I think you gave the correct answer.

Why would only 50% pass through the polarizer (eraser)? it is because only the ones that are (say) left handed (or only right handed) polarized will pass?

That's a classical result (observation) of Malus, in practice it will probably be less than 50%.

But the mechanism involved has no classical explanation at the fundamental level, and requires at least QED so certainly has only a probabilistic interpretation as far as we know.

 

[San K]

nice link ...explains the reason...thanks

maybe only the ones (p photons) that co-relate (support) the interference pattern (of s photons) will pass through the polarizer.

thus this is no "changing the past" happening in DCQE.

i.e. the moment any of the photons (s or p) is detected...the story has been fixed...the behavior of the other entangled particle is now fixed...

 

[unusualname]

nice link ...explains the reason...thanks

maybe only the ones (p photons) that co-relate (support) the interference pattern (of s photons) will pass through the polarizer.

thus this is no "changing the past" happening in DCQE.

i.e. the moment any of the photons (s or p) is detected...the story has been fixed...the behavior of the other entangled particle is now fixed...

No I don't think any changing of the past is possible either, but I rather think there is a simpler explanation: nature simply encodes the entire experimental set nonlocally via the wavefunctions involved, even if you stick the eraser near alpha centauri, so at the time the signal photons get detected nature "knows" whether the eraser is in place or not.

Of course the standard copenhagen explanation is that you should not try to analyse what happens in between measurements, but geez, that's so old (literally )

 

[JesseM]

No I don't think any changing of the past is possible either, but I rather think there is a simpler explanation: nature simply encodes the entire experimental set nonlocally via the wavefunctions involved, even if you stick the eraser near alpha centauri, so at the time the signal photons get detected nature "knows" whether the eraser is in place or not.

But you could decide whether or not to place the eraser after the signal photons have been detected, and the total collection of signal photons behaves exactly the same regardless of whether the eraser is in place or not...if you want to explain it non-locally, might be better to say each idler photon "know" the position that its entangled signal photon was detected, and adjusts its probability of being detected at various locations accordingly.

 

[unusualname]

But you could decide whether or not to place the eraser after the signal photons have been detected, and the total collection of signal photons behaves exactly the same regardless of whether the eraser is in place or not...if you want to explain it non-locally, might be better to say each idler photon "know" the position that its entangled signal photon was detected, and adjusts its probability of being detected at various locations accordingly.

That experiment has not been done afaik, I will not search now, since I am pretty sure if it was done the result would be no interference pattern in the dataset before the polariser is put in place.

In fact I would bet that if the polariser (eraser) was put in place just before the idlers arrived (but after the signal photons had been detected) there would be no interference pattern in the coincidence match.

There is talk of improving on the canary islands transit times with satellites in space, so this may be a doable experiment soon

 

[JesseM]

That experiment has not been done afaik, I will not search now, since I am pretty sure if it was done the result would be no interference pattern in the dataset before the polariser is put in place.

There's never an interference pattern in the signal photon dataset before you look at subsets of signal photons whose idlers were detected at particular positions, regardless of whether you measure the idlers before or after the signal photons, or whether the eraser is or isn't in place. The total pattern of signal photons is always the same, and it's always a non-interference pattern. Do you disagree?

 

[unusualname]

There's never an interference pattern in the signal photon dataset before you look at subsets of signal photons whose idlers were detected at particular positions, regardless of whether you measure the idlers before or after the signal photons, or whether the eraser is or isn't in place. The total pattern of signal photons is always the same, and it's always a non-interference pattern. Do you disagree?

Of course. But aren't we talking about a situation where the coincidence matching must be done with a timing offset (ie not a standard coincidence counter). Otherwise how can you talk about the placement of the polariser (eraser) after the signal photons have been detected? And obviously we'd like long enough time frames so as not to involve SR arguments about time orderings.

 

[JesseM]

Of course. But aren't we talking about a situation where the coincidence matching must be done with a timing offset (ie not a standard coincidence counter). Otherwise how can you talk about the placement of the polariser (eraser) after the signal photons have been detected?

Yes, the coincidence matching would have to be done using timing. But if you're agreed on the total pattern of signal photons never showing interference, why did you say "That experiment has not been done afaik, I will not search now, since I am pretty sure if it was done the result would be no interference pattern in the dataset before the polariser is put in place"? When you said "the result would be no interference pattern", were you not talking about the total pattern of signal photons? If you were talking about the total pattern, why bother noting this would be true in my suggested experiment, since it's true in all such experiments? And if you weren't talking about the total pattern, were you claiming that even after coincidence matching we wouldn't see an interference pattern?

By the way, note that an experiment where the idlers were detected after the signal photons has in fact been done, see the top of p. 2 of this paper which says:

The experiment is designed in such a way that L0, the optical distance between atoms A, B and detector D0, is much shorter than Li, which is the optical distance between atoms A, B and detectors D1, D2, D3, and D4, respectively. So that D0 will be triggered much earlier by photon 1.

 

[unusualname]

Yes, the coincidence matching would have to be done using timing. But if you're agreed on the total pattern of signal photons never showing interference, why did you say "That experiment has not been done afaik, I will not search now, since I am pretty sure if it was done the result would be no interference pattern in the dataset before the polariser is put in place"? When you said "the result would be no interference pattern", were you not talking about the total pattern of signal photons? If you were talking about the total pattern, why bother noting this would be true in my suggested experiment, since it's true in all such experiments? And if you weren't talking about the total pattern, were you claiming that even after coincidence matching we wouldn't see an interference pattern?
:

I think we must have had a confusion, I am ALWAYS assuming coincidence matching of the signal/idler pairs, but in the scenario you suggested (the polarizer is not physically in place when the signals hit their detector) then you have some apparatus or human hand to put the polarizer in place after a few miillisecs/minutes/years and then coincidence match based on flight time of the photons (of course this is very difficult in practice, but in space with satellites the transit times will not be too disturbed)

You see, I am saying that nature "knows" the whole arrangement of the universe at every instant, via what is encoded in wavefunctions.

 

[unusualname]

By the way, note that an experiment where the idlers were detected after the signal photons has in fact been done, see the top of p. 2 of this paper which says:

Yes, but I'm talking about something much more interesting, whereby the physical layout of the experiment is altered during the transit of the photons.

 

[JesseM]

Yes, but I'm talking about something much more interesting, whereby the physical layout of the experiment is altered during the transit of the photons.

But would you expect any different results in this case? It seems to me that in that experiment, with a large enough delay you could have the option of either removing the beam-splitters BSA and BSB (so that all idlers went to the which-path preserving detectors D3 and D4) or replace them with mirrors (so that all idlers went to the which-path erasing detectors D1 and D2), I would still expect the coincidence graph between the signal photon detector D0 and any specific idler detector to be unchanged from what it is in the paper (for example the D0/D3 coincidence graph would still be a non-interference pattern, the D0/D1 coincidence graph would still be an interference pattern). Would you predict something different, and if so why?

 

[unusualname]

But would you expect any different results in this case? It seems to me that in that experiment, with a large enough delay you could have the option of either removing the beam-splitters BSA and BSB (so that all idlers went to the which-path preserving detectors D3 and D4) or replace them with mirrors (so that all idlers went to the which-path erasing detectors D1 and D2), I would still expect the coincidence graph between the signal photon detector D0 and any specific idler detector to be unchanged from what it is in the paper (for example the D0/D3 coincidence graph would still be a non-interference pattern, the D0/D1 coincidence graph would still be an interference pattern). Would you predict something different, and if so why?

I'm sure it would be different, I would expect no interference pattern if mirrors were in place when the signal photons were detected, even if beam splitters were then swapped over before the idlers arrived.

(I haven't taken time to analyse the setup in detail so there may be irrelevant practical issues here)

You see, THIS experiment has not been done yet, the best they can manage so far with the Canary Islands experiments is far too small time delay to allow sufficent idler/signal pair production AND altering physical layout of the experiment.

Mankind should be ashamed that they cannot commit resources to space experiments to investigate all this, maybe the silly "don't ask" copenhagen interpretation is to blame.

 

[JesseM]

I'm sure it would be different, I would expect no interference pattern if mirrors were in place when the signal photons were detected, even if beam splitters were then swapped over before the idlers arrived.

Why would you expect that? Keep in mind that the setup of the experiment is such that with mirrors in place, the idlers can still end up in one of two detectors D1 and D2, and although the D0/D1 coincidence graph and the D0/D2 coincidence graph both are interference patterns, the two interference patterns are offset so the peaks of one line up with the valleys of the other and vice versa, meaning that the sum of these two interference patterns (which would be the total pattern of signal photons, assuming every idler was detected at one of those two detectors) ends up being a non-interference pattern.

 

[unusualname]

Why would you expect that? Keep in mind that the setup of the experiment is such that with mirrors in place, the idlers can still end up in one of two detectors D1 and D2, and although the D0/D1 coincidence graph and the D0/D2 coincidence graph both are interference patterns, the two interference patterns are offset so the peaks of one line up with the valleys of the other and vice versa, meaning that the sum of these two interference patterns (which would be the total pattern of signal photons, assuming every idler was detected at one of those two detectors) ends up being a non-interference pattern.

Look, this is going to be pointless, I don't like these multiple path experiments because they just convolute what is the simple issue under test "are wavefunctions non-local?". Some undergrad students led by Walborn did a far superior experiment to all the other rubbish published, and got it published it phys rev, it clearly demonstrates the nonlocality of wavefunctions without involving convoluted rubbish that can be semi-interpreted classically (they just use polarisation entanglement between SPDC pairs). Since we don't know what is going on in QM we should make our experiments as simple as posssible, Walborn et al managed that others didn't.

If you want to know exactly how I think it works, look at my home page.

 

[JesseM]

Look, this is going to be pointless, I don't like these multiple path experiments because they just convolute what is the simple issue under test "are wavefunctions non-local?".

I don't know what you mean when you say you "don't like" the experiments, whether you like them or not you can't escape the fact that they could be physically realized and would have to yield some definite results! So I assume you'd agree that there is going to be some definite prediction by QM about what the actual observed results would be, and a definite truth about whether QM's predictions are correct or not if we actually do the experiment, right? The question of what the observed results will be doesn't depend on any issues of your interpretation of QM like whether you think there is anything "non-local" going on (the many-worlds interpretation would purport to explain the results without non-locality, for example). So are you saying you think orthodox QM is incorrect in its predictions, or are you disagreeing with me that orthodox QM would predict we do see interference in the D0/D1 and D0/D2 coincidence graphs individually even when the beam-splitters are replaced by mirrors, or something else?

Some undergrad students led by Walborn did a far superior experiment to all the other rubbish published, and got it published it phys rev, it clearly demonstrates the nonlocality of wavefunctions without involving convoluted rubbish that can be semi-interpreted classically (they just use polarisation entanglement between SPDC pairs). Since we don't know what is going on in QM we should make our experiments as simple as posssible, Walborn et al managed that others didn't.

The Walborn experiment could also presumably be interpreted in a local way by many-worlds advocates, and in any case it doesn't tell me why you said "I'm sure it would be different" when I raised the issue of replacing the beam-splitters with mirrors in the delayed choice quantum eraser experiment where the idlers are detected after the signal photons (which does not appear to be the case in the Walborn experiment)

 

[unusualname]

I don't know what you mean when you say you "don't like" the experiments, whether you like them or not you can't escape the fact that they could be physically realized and would have to yield some definite results! So I assume you'd agree that there is going to be some definite prediction by QM about what the actual observed results would be, and a definite truth about whether QM's predictions are correct or not if we actually do the experiment, right? The question of what the observed results will be doesn't depend on any issues of your interpretation of QM like whether you think there is anything "non-local" going on (the many-worlds interpretation would purport to explain the results without non-locality, for example). So are you saying you think orthodox QM is incorrect in its predictions, or are you disagreeing with me that orthodox QM would predict we do see interference in the D0/D1 and D0/D2 coincidence graphs individually even when the beam-splitters are replaced by mirrors, or something else?

The Walborn experiment could also presumably be interpreted in a local way by many-worlds advocates, and in any case it doesn't tell me why you said "I'm sure it would be different" when I raised the issue of replacing the beam-splitters with mirrors in the delayed choice quantum eraser experiment where the idlers are detected after the signal photons (which does not appear to be the case in the Walborn experiment)

Ok, personally (and controversially) I think many of the people who attempt to examine QM foundations are not really doing it very well (to be blunt I would say they are, perhaps "dumb").

The many-world scenario is (I think) a cop-out without much predictive payback.

I suggest, accept an ontological probability, and a (schroedinger) determistic evolution, and volia, you have reality

 

[San K]

But you could decide whether or not to place the eraser after the signal photons have been detected, and the total collection of signal photons behaves exactly the same regardless of whether the eraser is in place or not...if you want to explain it non-locally, might be better to say each idler photon "know" the position that its entangled signal photon was detected, and adjusts its probability of being detected at various locations accordingly.

Agree. This is what I have been saying as well. The idler is effected by the detection of signal photon.

The wave function collapses, the behavior of the idler is now "somewhat" fixed.

somewhat fixed = probabilistically fixed...thus

In fact you can predict (with probabilities) how the idler would behave (which path it will take with what probability etc.) based on the position/location of the s photon on Ds.

 

[JesseM]

Ok, personally (and controversially) I think many of the people who attempt to examine QM foundations are not really doing it very well (to be blunt I would say they are, perhaps "dumb").

The many-world scenario is (I think) a cop-out without much predictive payback.

I suggest, accept an ontological probability, and a (schroedinger) determistic evolution, and volia, you have reality

But Schroedinger evolution is just for the state vector with complex amplitudes, in order to get real-valued probabilities in a non-MWI scenario you either need to ditch the state vector (replacing it with some hidden variable state as in Bohmian mechanics) or you need to include periodic "collapse" due to measurement, and then you have to explain what exactly causes the "collapses" to occur if you want to say that the measuring-system obeys the same laws as the system being measured.

In any case, my question wasn't about interpretational issues, I specifically said I was just asking if you agree or disagree with me about what orthodox QM would predict about measurable outcomes in the delayed choice quantum eraser when the beam-splitters are replaced by mirrors. All the different "interpretations" are supposed to agree with orthodox QM in their predictions about the statistics of actual measured outcomes...

 

[San K]

No I don't think any changing of the past is possible either, but I rather think there is a simpler explanation: nature simply encodes the entire experimental set nonlocally via the wavefunctions involved, even if you stick the eraser near alpha centauri, so at the time the signal photons get detected nature "knows" whether the eraser is in place or not.

Of course the standard copenhagen explanation is that you should not try to analyse what happens in between measurements, but geez, that's so old (literally )

The eraser is stuck after the s-photons have been detected...say 5 seconds later, if I understand the experiment correctly.

Thus "nature" would not know if there is an eraser or not, when s photon stuck.

Thus the sequence could be ...

10 am --- s photon detected on Ds
10:00:05 am --- erasure put in path of p-photon (idler)
10:00:10 am --- p-photon detected on Dp

Let me go through the your and other posts and I will post again.

 

[unusualname]

But Schroedinger evolution is just for the state vector with complex amplitudes, in order to get real-valued probabilities in a non-MWI scenario you either need to ditch the state vector (replacing it with some hidden variable state as in Bohmian mechanics) or you need to include periodic "collapse" due to measurement, and then you have to explain what exactly causes the "collapses" to occur if you want to say that the measuring-system obeys the same laws as the system being measured.

In any case, my question wasn't about interpretational issues, I specifically said I was just asking if you agree or disagree with me about what orthodox QM would predict about measurable outcomes in the delayed choice quantum eraser when the beam-splitters are replaced by mirrors. All the different "interpretations" are supposed to agree with orthodox QM in their predictions about the statistics of actual measured outcomes...

Nope, the experiment has to be set up properly to disallow crap that the naysayers might argue, the only one that does this is the Walborn experiment, the rest try to "test too much".

The Walborn experiment should be done in space, and watched on live tv, and everyone should be made to see how nature encodes the entire universe every instant.

If I wanted JesseM, I could argue about your experimental observations, but it's not what I do, I think I have mentioned some modern experiments that mankind is attempting and compared to that your stuff seems in the past.

Qm is tricky, and I don't do silly arguments any more, even if they are (in your case) well thought out and rational.

Really, your analysis and observations about the experiments are graet

 

[San K]

I'm sure it would be different, I would expect no interference pattern if mirrors were in place when the signal photons were detected, even if beam splitters were then swapped over before the idlers arrived.

(I haven't taken time to analyse the setup in detail so there may be irrelevant practical issues here)

You see, THIS experiment has not been done yet, the best they can manage so far with the Canary Islands experiments is far too small time delay to allow sufficent idler/signal pair production AND altering physical layout of the experiment.

Mankind should be ashamed that they cannot commit resources to space experiments to investigate all this, maybe the silly "don't ask" copenhagen interpretation is to blame.

The experiment has been done. Its done, almost all the time, in DCQE. Also Jesse has provided another way/modification to show how it can be done.

The results are contrary to what you would wrote above.

 

[JesseM]

Nope, the experiment has to be set up properly to disallow crap that the naysayers might argue, the only one that does this is the Walborn experiment, the rest try to "test too much".

"Nope" to what? Do you disagree that the experiment I describe must have some definite outcome, regardless of whether you consider the setup to be "proper" according to whatever your unstated criteria are?

The Walborn experiment should be done in space, and watched on live tv, and everyone should be made to see how nature encodes the entire universe every instant.

The claim that it "encodes the entire universe every instant" is a matter of interpretation, the experiment won't prove anyone interpretation since they all are supposed to agree in their predictions about observable outcomes.

If I wanted JesseM, I could argue about your experimental observations, but it's not what I do, I think I have mentioned some modern experiments that mankind is attempting and compared to that your stuff seems in the past.

If you don't want to discuss experimental observations now that's fine, but you seem to have been talking about them before when you disagreed with my comments about the observation of interference by saying "I'm sure it would be different, I would expect no interference pattern if mirrors were in place when the signal photons were detected, even if beam splitters were then swapped over before the idlers arrived." "I would expect no interference pattern" is a statement about what would be observed, not about how we interpret our observations. If you don't want to stand by that statement no problem, but that was the statement that led to this particular tangent of the discussion.

 

[unusualname]

The experiment has been done. Its done, almost all the time, in DCQE. Also Jesse has provided another way/modification to show how it can be done.

The results are contrary to what you would wrote above.

No it hasn't been done, the experimental apparatus has not been altered during the flight time of the photons on a delayed choice experiment (it happens in aspect's experiments, a single photon at a time).

In delayed choice experiments you need an accumulation of paired photons from SPDC to match, no one has a more clever method.

I don't really like "this is wrong" posts, when what I've posted clearly is correct, if you are a noob, stand back and observe please.

JesseM has an agenda which I will easily defeat if he persists in this thread, since I know he cannot be correct.

 

[unusualname]

If you don't want to discuss experimental observations now that's fine, but you seem to have been talking about them before when you disagreed with my comments about the observation of interference by saying "I'm sure it would be different, I would expect no interference pattern if mirrors were in place when the signal photons were detected, even if beam splitters were then swapped over before the idlers arrived." "I would expect no interference pattern" is a statement about what would be observed, not about how we interpret our observations. If you don't want to stand by that statement no problem, but that was the statement that led to this particular tangent of the discussion.

Ok, I didn't even look at the experiment, maybe I got something mixed up, but understand this: if the setup is changed during the flight time of the photons you have no friggin idea do you, whereas I can EXACTLY explain it.

 

[JesseM]

Ok, I didn't even look at the experiment, maybe I got something mixed up, but understand this: if the setup is changed during the flight time of the photons you have no friggin idea do you, whereas I can EXACTLY explain it.

"No friggin idea" about what? I think any experiment involving correlations between entangled particles has potential to be explained locally via a many-worlds type interpretation, see [post=1557143]this post of mine[/post] for a simple "toy model" explaining conceptually how this could work. I looked at your webpage and you don't seem to have a very clear model, you seem to include some concept of "collapse" but you don't seem to give an answer to the problem I raised earlier about models with collapse:

then you have to explain what exactly causes the "collapses" to occur if you want to say that the measuring-system obeys the same laws as the system being measured.

And from your non-response to my comment about your statement "I'm sure it would be different, I would expect no interference pattern if mirrors were in place when the signal photons were detected, even if beam splitters were then swapped over before the idlers arrived", I take it you are indeed abandoning this claim, but for some reason are refusing to acknowledge this explicitly? There's no shame in retracting a statement you made too hastily y'know, everyone does this from time to time, but it's kind of odd when someone is repeatedly pressed on a comment but they just won't say anything more about it one way or the other.

 

[unusualname]

"No friggin idea" about what? I think any experiment involving correlations between entangled particles has potential to be explained locally via a many-worlds type interpretation, see [post=1557143]this post of mine[/post] for a simple "toy model" explaining conceptually how this could work. I looked at your webpage and you don't seem to have a very clear model, you seem to include some concept of "collapse" but you don't seem to give an answer to the problem I raised earlier about models with collapse:And from your non-response to my comment about your statement "I'm sure it would be different, I would expect no interference pattern if mirrors were in place when the signal photons were detected, even if beam splitters were then swapped over before the idlers arrived", I take it you are indeed abandoning this claim, but for some reason are refusing to acknowledge this explicitly? There's no shame in retracting a statement you made too hastily y'know, everyone does this from time to time, but it's kind of odd when someone is repeatedly pressed on a comment but they just won't say anything more about it one way or the other.

The point is I could not be bothered with your experiment you linked to, really, is it that different to any other **** we've been subjected to over the years?

If this was my first or early response, on the forum of course it would be rude, but it's not, I've argued out (practically alone) the unbelievers on the quantum physics forums for over a year
. You've stood there in the sidelines with your hope for everett mwi, but come on, man up, I know you're on my side but you don't like the cak-handed way I'm doing it. I*'m sure you think I've surely got it.

The reason I can't argue your experiments is because there are a lot or classical conditions with phase relationships and absorption/reflection laws that can brought into play to really complicate things, and I don't want to do that (because it's pointless). Better two satellites in space in something like the Walborn setup with polarisers placed during the transit time of the photons.

 

[JesseM]

f this was my first or early response, on the forum of course it would be rude, but it's not, I've argued out (practically alone) the unbelievers on the quantum physics forums for over a year
. You've stood there in the sidelines with your hope for everett mwi, but come on, man up, I know you're on my side but you don't like the cak-handed way I'm doing it. I*'m sure you think I've surely got it.

On your side about what? I don't like any interpretation that treats "collapse" as real, seems absurd to me given what's known about decoherence.

The reason I can't argue your experiments is because there are a lot or classical conditions with phase relationships and absorption/reflection laws that can brought into play to really complicate things, and I don't want to do that (because it's pointless). Better two satellites in space in something like the Walborn setup with polarisers placed during the transit time of the photons.

I don't get it, what "classical conditions" would be in the delayed choice quantum eraser (feel free to assume it's performed in space too) that wouldn't be in the Walborn setup?

 

[unusualname]

On your side about what? I don't like any interpretation that treats "collapse" as real, seems absurd to me given what's known about decoherence.

I don't get it, what "classical conditions" would be in the delayed choice quantum eraser (feel free to assume it's performed in space too) that wouldn't be in the Walborn setup?

The walborn setup doesn't allow any possibility of classical phase relationships being in any way significant