the underlying assumptions rig the debate

Who is the informed observer here? They were not informed of the knowledge of good and evil, and of death, but then they did gain knowledge of it, the world had changed.But regardless, the primary point of evos assuming a static past has been successfully refuted as the past responds based on what can be known about it.

As I have pointed out to you guys ad nauseum, the experiments were done in this world, not as mere thought experiments, and not in math. It is, imo, intellectually dishonest to continually state that's because they are trying to render the math into English when that is not the case at all.What they are doing is describing the experiments in English. They are not trying to put the math into English when they say the photon "seems to know" and is time you guys quit making that claim.The math, like the English, is an attempt to explain the experiments and yes, the experiments do show certain mathematical principles, but when people say the photon "appears to know", they are describing the observed behaviour of the photon, not the math.Edited by randman, : No reason given.

On what basis is the jury out? Incredulity? And you think Wheeler had no theoritical or experimental support to make this claim? LOL. He made this claim because of the experiments. Why don't you substantiate what he did mean then? He was referring to himself and mainstream science when he made the statement, and that's because QM conflicts with other areas such as GR. No I am not, and the old argument that science fiction writers or others would be jumping up and down is getting old. I have showed you plenty of scientists that state the results clearly indicate that the present measurement determines whether the photon manifests as a wave or particle, and you know what, no one really disagrees with that actually. They don't want to come out with the implications of that, but no one out there really disagrees that these experiments do show that the form of measurement affects the photon's path even if the measurement was taken after the photon travelled it's path. That's why Wheeler made the comments he did, and others as well like Zeilinger.You just assumed that the spin you have heard from evos about QM was true when it has never been true. Oh, so if anyone runs a test for gravity, GR, or how about mutations, then by golly they must doubt the earlier claims are true? That's absurd. One reason they continue to run experiments with basic quantum mechanics is so we can develop a better technology in using it, and another is to settle the issue firmly and develop a more comprehensive theory of everything. For instance, there are experiments to see if larger objects can become entangled, have wave-like properties, etc,....so we can see to what degree QM principles work in the macro-world directly.

You seem to have missed the point. Let's imagine the scenario where the photon pass through some polarizers and so we could observe which path and they thus take one path. Now, there is the third polarizer that erases that collapse by scrambling the ability to know what path the photon took, but this time it is, say, a month of a light-year away. So a month later, the photons that did take a single path the month before, now in the past took all possible paths.See what I am talking about?The fact that an observation was made does not change the fact that down the road the same observation cannot be made. Just imagine the experiment more spread out distance-wise so you can properly assess how with the changes in time, the past can actually change. The photons can go from a collapsed state to a non-collapsed state IN THE PAST.Now, let's extend the experiment further. Let's say the photons travel another month, and this time are sent through a polarizer so we can determine which path the photons took. Then, they would collapse back to a single path again, but here is the kicker.What path would they exhibit?So you could have along this trajectory, 3 different pasts all observed by people. The first group observes a single path. The second group observes the photon as a wave, all paths taken, and the third observes a single path taken (and no reason to think it would be the same as the first group).

No, the quote was specifically about how the photon behaves in the 2-slit experiment; hence specifically about the appearance of causality in the experiments.

You are confusing issues here. You guys brought up superluminality, and that is indeed an area of research that is contested, but how a photon behaves in these experiments is a different issue. First off, QM predicted the behaviour, and repeated tests verify it. The behaviour indicates that if you can determine what path (in the past be definition) that a photon takes, then it takes (in the past) a single path (from our vantage point at a minimum).However, if you cannot tell which path (by definition in the past) a photon took, then the photon takes all possible paths (from our vantage point).So how you decide to measure determines the past in these experiments. That's something you need to understand because it's not really contested.There are ways though for physicists to interpret this to get around seeming backwards in time causality (even though some advance backwards in time causality with transverse waves), and one way is to claim the photon only appears to take one path but actually takes all possible paths. The Many-Worlds and Many-Minds interpretations do that, as well as perhaps some others such as claiming what we measure and see is not reality but merely phenomena associated with reality, which cannot be directly observed (Hologram and other approaches).But regardless, from a human perspective, how you question the photon and what can be known from the photon does determine whether in the observable world we live in, exactly what the photon did in the past. If you can know if it took a single path in the past, then in the past it takes a single path (even if it took all paths at one time, as shown in the quantum eraser experiment). if you cannot know, then the photon acts like a wave and the interference pattern appears.I strongly suggest before you keep bashing me that you take some time to get a handle on what is actually observed in these experiments.

And why did he not accept causality violations? You need to learn a bit more about the interpretations that avoid this somewhat obvious conclusion and also realize that some like Wheeler do talk about causality in a different way (in other words violating causality). Others like even PaulK here from his reading, presumably picked up from scientists, get around this by saying the past was indeterminate and so try to get around it that way.Iblis seemed to be saying that the photon still takes all possible paths even though it appears to only take one path when we can determine that path. Imo, this is sort of the same thing as I am saying since the universe we live in as human beings would have a multitude of pasts, that appear or disappear depending on our observations.Another way around the obvious causality from the present towards the past is similar, and to claim that not only do all pasts exist in superposition as possibles, but all exist as real (the Many-Worlds) and so one might try to get around the causality issue that way.The more mainstream way around it, advanced by Borh, was to deny physical manifestations are real. Under that scenario, all we can ask about reality is the phenomena, never dealing directly with the reality at all.But once again, however you want to spin this, the bottom line is the past we can measure or have experiences, etc,....is determined in part by the present knowledge we can have of it. You can find plenty of ways to say it is not the present having a causitive effect on the past, but in human terms, the past can and does change as demonstrated by these experiments.

cavediver, I think you are confusing the human concept of transfer with the concept of transferring some physical energy or something. Let's take your example as poor as it is and you acknowledge that. The big deal is that you instantly know the state of the other particle billions of light-years away, and the knowledge of that situation may well have been transferred from the box you have in front of you, but using this principle you can know something instantly about a box a billion light-years away.I think this process can be manipulated to convey information. Certainly, information was conveyed when the box was opened, wasn't it? You can say, yea, but scientifically no superluminal transfer occurred. Well, in this instance, I say so what?If you can devise a way to know something about something in a distant place, well, I think there is a potential to manipulate that process.The truth is information is transferred over space and time instantly all the time. Heck, when I read a history book, I am getting information about the past.But none of this really relates to the OP anyway.

First off, you ought to reread what PaulK stated before assuming I am mischaracterizing his statements. This what he said: You go on to say something that shows you have not understood my argument here: It doesn't matter what "you" know or don't know, or whether you ever had information or not. What matters, at least as it seems from these experiments, is what can be known at any point in time. So if one can know what path the photon already took, the photon will have taken a single path. If one cannot tell which path a photon takes, it takes all possible paths. This is shown in that when we change the test so we can know, the interference pattern disappears such that the photon travels as a particle, and when we change the measurement so there is no way to tell, the interference pattern reemerges so that photon took, in the past, all possible paths.Clearly then, the path the photon takes or took is determined by our approach to questioning it. Zeilinger points this out in suggesting that perhaps the photon is an "elementary particle" containing a bit of information, and when that information cannot be known, the bit is not spent and so the particle is superposition, but when it can be known, the particle's bit is spent, and so only one path is taken. Whether you agree with him, understanding why he advances a more developed version of Wheeler's It from Bit concept helps to understand the experiments. In other words, he is trying to solve a problem. Maybe if you consider his solution, you will see the problem I am talking about here.So let's take this further, along the path of a photon then, it may hit a spot due to circumstances that there is a means of registering the photon's path and so at that point, the photon in the past will have taken a single path. But later down the road, the means to determine which path the photon took could be erased or lost, and so the photon then, over the same stretch of space in the past, will have travelled in superposition and not a single path. In that manner, the past that we deal with does indeed demonstrably change.Whether someone knows about the path or not is not really germane to the discussion. In fact, the person that measures the photon when they can tell what it did will see the photon having taken only one path, and another person measuring the same photon but without the means even in principle of knowing from measurement what path the photon took, will see the same past as having shown the particle travel as a wave.Now you can debate how to solve this dilemna all you want, but pretending the dilemna isn't there is not a good argument, and that seems to be what you are doing. And the quantum eraser experiment shows that this decoherence is not permanent. That's a key point you are missing here.

That's correct, but you have to realize that "our information changes" includes the information about what constitutes the past.

This is a contradiction. You admit you can know what a particle's spin is on the other side of the universe; hence you can know something about a distant place. I am not ignorant one or the group of ignorant folks that claimed no respectable scientists were devoting resources to working on superluminality. You are in that group. The problem with me mocking you, as you try to do with me, is you are so ignorant and your side so stubborn that proving you wrong is like talking to a brick wall.Similarly, you fail to realize harnessing the principle of entanglement is in it's infancy. You assume that such and such cannot be done, and ridicule that, but in reality, there are scientists working to see if it can be done all the time. A few years ago, Hawkings said time travel was impossible, and now says that though unlikely, it is possible.Why do you think he said that, Percy? You think he's an ignorant fool as well since after all breaking the time barrier in this manner would constitute a total violation of the physical principles you claim cannot occur.Right now, we don't really understand fully the mechanism of entanglement and so it is foolish to say that this mechanism cannot be used for such and such. The truth is entanglement suggests there is a deeper structure within the universe that we presently are aware of. Cavediver himself has speculated along the lines of thinking in terms of a hologram right here on this thread. If that's the case, figuring out how the underlying reality generates this hologram could do a lot of things.Zeilinger stated that entanglement appears to work outside space and time. You think he is saying if it works outside space and time that he really believes it can never be used to do some things people say cannot be done? I don't. I am not sure if he would openly state that yet, but just mentioning it appears to involve a process outside space and time already says much the same thing as I am saying.Lastly, what does superluminality have to do with my arguments in the OP?Edited by randman, : No reason given.

You know darn well the issues I am bringing up are real, but all you do is scoff and throw mud, refusing to engage any of these issues with substance, imo.For example, I posted Zeilinger's statement that he considered the criterion for whether a photon behaved like a wave or particle to be what we could know, not the measurement itself, about the wave-function. That, on it's own, is an incredibly far-reaching comment clearly demonstrable in these experiments with or without any math being involved at all.Your comment?Nada, but derision. Well, I really don't care if it WAS your "f'ing profession". It IS his profession and I consider his statements much more significant than your BS derision about, hey, it's because you don't know the math, etc, etc,....especially when these are optical experiments done with apparatus, not simply math experiments.I throw a baseball through a window, and you can tell me I don't understand it all day long because I don't know the math behind the velocity, wind speed, curve, gravity, etc,..., but pretending I don't know the ball went through the window is ludicrous. Same with these experiments. Whatever labels you want to apply and whether or not what we observe is real or a holographic projection or whatever, the experiments do show a set of observed details.Most I have read indicate they believe the experiments do show that you measure the photon one way and it will show it behaved as a particle, and measure the other, and it will show it behaved as a wave. I think you know that, but just don't want to admit it.Next time you want to argue based on your resume, why don't you at least address the points that have been raised.Edited by randman, : No reason given.Edited by randman, : spelling and to place emphasis via quotation marks and caps

Another dodge by you. Typical. You know what the question entails. It entails 2 specific areas.1. If a present observation makes it clear that we can know what a photon's path is, it appears that the photon, prior to that observation even, follows a single route in a particle-like fashion as seen by no interference pattern.So does the wave-function encompass or however else you want to say it the points in time prior to the observation? The reason this is a suitable question is because the photon appears in our world to have taken only one path. Keep in mind I am not asking about the many interpretations of whether the photon really does take all paths, but we only see it take one path because of our perspective. I am just talking about the world from the human perspective. The photon's path, even in the past, appears to reflect whether we can have knowledge of that path, correct?Yes or no will suffice.2. When "2 particles", for sake of argument, are entangled, they act as one system, correct? At least in some aspects, right? So we can say the wave-function perhaps encompasses both particles or both separated photons as an example (separated meaning appearing so from our perspective). So does the wave-function apply or exist or whatever else you want to say to mean encompass both locations or not?Edited by randman, : No reason given.

Well, why do you make this statement. The thread is not about "superluminal transfer", is it? In fact, the thread has nothing whatsoever to do with the idea. I addressed it as a side issue, since you guys brought it up, but continually bring you back to the same points over and over again, only to have had you, imo, dodge them.Moreover, I have not stated even that there are superluminal particles, nor the opposite. Tachyons and things like that may be real or not. What I have stated is we have the likelihood of a deeper structure within the universe and you yourself speculated on additional dimensions. Now, since we don't know all about these dimensions, it is sort of silly, imo, to speculate that they cannot be used to cause things to occur in 4-D that otherwise would be impossible.But regardless, that's not what the thread is about, and you know that. The following comments do relate however to the thread. Fine, but it still leaves either an interference pattern or not in the world we live in, real or not. So are you saying all possible paths are always taken? Or are you saying the path of the photon prior to that point of observation is indeterminate? But it is our understanding of the past that this thread is about. That's something I think you are ignoring. Thank you. That was easy, right? So we have something that operates according to rules, but somehow in a mode that can be multi-locational. What do you mean by "evolve throiugh time"? When we observe via measurements that the photon behaved like a particle, the wave-function didn't really change, or did it? In other words, what we are seeing is a discrete form within the wave-function, right?Of course, maybe the It from Bit theory Zeilinger advances is right and it somehow did "spend" it's bit and evolved into a collapsed state. To be honest, I can't tell thus far where you stand on this.But let's say by evolve, you mean it "collapses" or however else you want to say it, so that it from our measurements, one path is taken. That is due to the potential knowledge of it's path as the determining criteria, right?Or do you disagree with that?OK, let's say then that this changes and the ability to know what path the particle takes is scrambled, the particle then shows an interference pattern, right? Indicating wave-like propagation, right?Well, looking at the quantum eraser experiment, what is the distance between when the particle can be measured and when the particle could not be measures was, say, a light-year apart. Isn't it true that someone that would observe or measure the photon in the first year see it taking a single route as a particle, and the person in the 2nd year would see it as taking all possible routes. So looking back on the same event, the photon's path, from 2 vantage points in time yields differing "realities", one with the photon taking one path and another with the photon taking all paths, right?Edited by randman, : No reason given.

You guys are the ones that bring up superluminality, not me, percy.Moreover, you are ignoring this statement by Wheeler: Cosmic Search Vol. 1, No. 4 - FORUM: John A. WheelerRather than pretend he didn't say this, or doesn't believe this, or trump up some unrelated BS about Paul Davies that has no relevance whatsoever, why don't you take a stab at explaining what you think Wheeler meant?You are fond of saying no scientist says what I am saying, and yet right here Wheeler advances the observer-participancy principle, and repeats one of his sayings: What experimental basis do you think he is alluding to when he says this is "the absolutely central point of the quantum:".You keep telling me it isn't the central point of the quantum. Well, tell me why I should believe you. Tell me what you think Wheeler is really saying. Post something of substance related to the experiments he draws this from, please.Edited by randman, : No reason given.