Talk:Afshar experiment/Archive 22

Archive 15

←

Archive 20

Archive 21

Archive 22

Archive 23

Archive 24

Archive 25

Peer-reviewed paper

FYI: The main peer-reviewed paper on my experiment will be published in Foundations of Physics, February 2007 edition and the paper is currently available in the "Online First" section of the journal. It is titled Paradox in Wave-Particle Duality DOI 10.1007/s10701-006-9102-8. I suggest the interested parties read this paper and respond accordingly. I will shortly post a non-copyright version of the paper in arXiv. Best regards. -- Prof. Afshar 06:11, 26 January 2007 (UTC)

The peer-review itself is not a guarantee that published work is not nonsense, see Bogdanov Affair. Danko Georgiev MD 06:29, 26 January 2007 (UTC)

"It's not peer reviewed" yelled everyone. Now it is about to be, they yell "peer review does not mean anything". This is another new form of complementarity, obviously... You can't have peer review and have peer review be worth anything at the same time. Dndn1011 09:05, 26 January 2007 (UTC)

FYI I welcome peer review, since it will generate a host of peer-reviewed rebuttals. --Michael C. Price ^talk 12:30, 27 January 2007 (UTC)

While peer review is never a gaurantee of perfection, at the very least a peer reviewed paper is verifiable. We can use this, then, as a starting point for the article. It is always better to use papers which have been peer reviewed instead of papers which are not, I hope we can agree. --ScienceApologist 08:30, 26 January 2007 (UTC)

There already is an article. Now it can become an article with peer reviewed sources, which in reality just makes it more notable. It was already verifiable, having been previously been in print. Additionally it is always best for people to use their own judgement. The facts have not changed just because the experiment has finally managed to work its way through a bureaucratic system. Dndn1011 09:05, 26 January 2007 (UTC)

Afshar was directly asked to prove that there is which way information, since already 3 verifiable papers prove the opposite. Instead Afshar says "look at my peer-reviewed paper", but instead of explanations, Afshar uses self-citations with missing explanations. The only text in the whole paper (in Foundations of Physics journal) that must supply the necessary argument is this one

"In the far field beyond the region of overlap, the beams maintained their which-way information due to the law of conservation of linear momentum.(19,20). References: 19. S. S. Afshar, Violation of Bohr’s complementarity: one slit or both?, AIP Conf. Proc. 810, 294–299 (2006); http://www.irims.org/quant-ph/040901 ; http://arxiv.org/abs/quant-ph/0701028 , 20. S. S. Afshar, Experimental violation of complementarity: reply to critics, submitted to Frontier Perspectives; http://www.itims.org/quant-ph/070101 "

Note that the web-link of ref.(20) even does not work, while the second link of ref.(19) refers to paper that is not published by Afshar, and no obvious connection to the topic is seen - "First order quantum phase transitions in the XX spin chain", even if those are typos, nothing clear up to far!

Thus Afshar self-quotes himself and defers the discussion to other preprints, lectures, future publications, etc. Prof. Qureshi already told Afshar that the linear momentum argument itself is invalide, so unless Afshar provides something more, his deferring scientific discussion is obvious. Danko Georgiev MD 10:43, 26 January 2007 (UTC)

No one is in the position to ask anyone else to "prove" anything. We are here to write an article based on verifiable and reliable sources. Nothing more. Afshar, like yourself and all other contributors, is merely volunteering his time to help us summarize the sources we can find for the materials. Your opinions about "self-citations" and "missing explanations" is noted, but it isn't verifiable or reliable unless you source it using the rules outlined in the guidelines and policies I linked to. What I'm saying is, you should try to reformulate your argument. Instead of attacking Afshar's abilities or his advocacy as you might during a rhetorical debate, you should simply refer to sources -- and the more accessible the sources the better. --ScienceApologist 20:22, 26 January 2007 (UTC)

Please, Danko, if you continue making personal attacks you will find yourself on the wrong end of an administrative sanction. Just discuss the material and not the people. Thanks. --ScienceApologist 09:33, 26 January 2007 (UTC)

Dear ScienceApologist, I have myself additioanlly censored the text. Danko Georgiev MD 10:43, 26 January 2007 (UTC)

Thank you. This will only help matters. --ScienceApologist 20:24, 26 January 2007 (UTC)

If the linear momentum argument itself is nonsense, then this means that the concept of which way is also nonsense. Afshar appears to be highlighting a paradox. The paradox appears clear, and the only argument being used against this view is a logical one that apparently proves that which-way information is not retained. In fact this counter view is just one side of the paradox. On the other hand we have those who use their eyes and see that the photons appear to come from one slit or the other. It is not nescessary for Afhsar to prove that the target hit corresponds to the hole the photon went through. We all can see that is impossible. That's the nature of paradox. If the target hit is no indicator of which hole the photon went through, then just what is it that it indicates? At what point does the photon stop being a wave and start being a particle? At the slits? At the wires? In the lens? It seesm quite clear to me that the only way to resolve this is to say that the photon exists as a probability field until it is measured. In this way, there is no which-way because during the time from emission to detection, the photon does not exist as a particle, but as a probability function. The only time that we can know where the photon actually is, is at the moment of measurement, at which point it ceases to exist. Now there is no paradox, and no need for the principle of complementarity either. Dndn1011 09:43, 26 January 2007 (UTC)

Dear Dndn1011, mathematically the "which way" is equivalent with existent one-to-one correspondence in the way slit1 <-> detector1, slit2 <-> detector2, and you cannot simply say that "which way is nonsense". Either there is one-to-one correspondence, or there is no one-to-one correspondence. Don't confuse the absence of which way information (one-to-one correspondence) with nonsense. There are quantum experiments in which the which way one-to-one correspondence can be proved mathematically - these setups are characterized with incoherent superpositions, described by mixed density matrix, i.e. off-diagonal elements of the matrix that are responsible for the interference effects are absent. So complementarity is not violated - erase the off-diagonal elements of the matrix and you get the which way, allow the off-diagonal matrix elements to exist (existent interference) and you lose the which way. Danko Georgiev MD 10:31, 26 January 2007 (UTC)

Actually, it is a bit more subtle than you make it out to be. Quantum mechanics does not specify a binary one-to-one or not one-to-one relationship for experiments. In fact, complimentarity itself says that there is a spectrum of results that can happen. --ScienceApologist 20:22, 26 January 2007 (UTC)

I admit that this is very close to the sense I got upon first reading the information regarding this page. The principle of complementarity is something which doesn't appear or at the very least is extremely marginalized in very many classic quantum mechanical texts published in the last ten years or so. All of the quantum mechanics I have worked with assumes the existence of waveparticles which only behave as one phenomenon or the other according to a collapse of a wavefunction to a delta-function in either position (for a 'particle') or momentum (for a 'wave') space. Complimentarity here occurs just because the Fourier transform of position is momentum and vice versa. But Afshar isn't contradicting this sense of complimentarity. --ScienceApologist 10:13, 26 January 2007 (UTC)

Exactly, since the quantum formalism is obeyed, complementarity is not violated. --Michael C. Price ^talk 11:59, 26 January 2007 (UTC)

Ironically, though we are in agreement on this point I see it as meaning that there isn't anything all that "controversial" about the Afshar experiment in my mind. However, I believe you have a different take on the matter. --ScienceApologist 20:22, 26 January 2007 (UTC)

No, that is exactly how I see it as well. The experiment obeys the formalism, ergo complementarity is obeyed; end of story. This is really a null experiment. No shocks, no upsets. Nothing to cause Bohr to spin in his grave. --Michael C. Price ^talk 21:31, 26 January 2007 (UTC)

Well, we can't exactly go an ask Bohr what he thinks, so that sort of speculation is best left either to verifiable quotes or removed completely from the article. --ScienceApologist 22:18, 26 January 2007 (UTC)

Indeed, which is why I inserted a verifiable quote from Bohr on this specific issue into the critique section. "Niels Bohr stated "an adequate tool for a complementary way of description is offered precisely by the quantum-mechanical formalism" " --Michael C. Price ^talk 22:41, 26 January 2007 (UTC)

It is not that one cannot ever vrirfy if there is a which-way info in Afshar's experiment. There IS a way one can verify it. Suppose we set the source of light in such a way that the amplitude at one slit is larger than that from the other slit. Of course the dark fringes will not be perfectly dark in this case. But we block the dark part by wires. Now Afshar, or anybody who thinks there is which-way info, will expect that one detector will receive larger intensity than the other, because one slit sends light with a larger amplitude. But look at the equation which I write down on this page before
$\psi (x)={a+b \over 2}\exp(ikx)+{a+b \over 2}\exp(-ikx)+i(a-b)\sin(kx)$
The sin(kx) term is what is the dark part, and we have blocked it. The other two parts, going to two different detectors are OF THE SAME INTENSITY! Afshar can easily verify this in his experiment.
NOTE: This is clearly OR!--Tabish q 12:51, 26 January 2007 (UTC)

What I would like clarification on is why interference-effects is all we're concerned with here. I believe that you are arguing that the experimental set-up demands this. Is that a fair characterization? --ScienceApologist 20:22, 26 January 2007 (UTC)

Sorry, either you are all mad or I am. Or if I create my own reality, we are all mad. (That was a joke). It's just that no-one ever actually answers the points I raise. Everyone is just stuck with their views. Danko's view is true!=false. Price's view is true=true. Tablish's view is somwhat confused but might be false=false. Tablish's last argument is flawed in any case because once interference takes place there can be no whichway information. How can there be which way information for any photon that has to interact with both slits? It is not possible. Also one has to be carefull about what "larger amplitude" means. It just means fewer more photons. I believe that it will be seen that fewer photons will be received by the detector corresponding to the hole through which less light travels. The effect will be to weaken the interference pattern. The extreme case is where no photons pass through one hole, because the hole is closed. If the holes are of different sizes you will see a different number of photons detected on each detector. How can it not be so? Dndn1011 14:40, 26 January 2007 (UTC)

I think you may have a fair summary here, but again I think that some of this confusion comes from not agreeing on the experimental set-up itself. What do you think? --ScienceApologist 20:22, 26 January 2007 (UTC)

Dear Dndn1011, your post is not understandable at all, but I admire prof. Qureshi's new example - brilliant. It shows a verification of my earlier posts in Wikipedia (archived somewhere) that unbalanced coherent passage through two pinholes for example 40%/60% cannot be interpreted as a statistical mixture 40%/60% in which one insists that 40% of photons have passed pinhole 1, and 60% have passed pinhole 2. In contrast the truth is that in the coherent case the photon's pass through both pinholes in unbalanced fashion 0.63/0.77 (taken the square roots)! Prof. Qureshi is clear - if Afshar interpretation were true if in the unbalanced setup there were both interference + which way as Afshar claims, then the wires placed at the almost dark fringes will absorb only small amount of light, but the images at the detectors will be expected to remain unbalanced 40%/60% (the which way claim). Yet prof. Qureshi shows that the detectors will detect 50%/50% in contrast with the which way expectation. Afshar thesis is wrong, and he cannot explain this new experiment with his new interpretation. The accumulating evidence against Afshar comes from many different lines of thought, so the earlier he sees his own error, the better for him. I personally vote prof. Qureshi to include himself this example in the main article with detailed explanation. Possible inclusion of graphics of the "expected" unbalanced intensity at the detectors, and in contrast the "real" 50/50 detection must be convincing for everybody. Danko Georgiev MD 14:57, 26 January 2007 (UTC)

Dear Danko, it may be that the problem is that I am not expressing myself properly. I shall at some point do a piece on the futility of thinking of paths of photons (and indeed which-way). I have not had enough valid feedback as yet from people to see whether or not they are missing the paritcular insight that I am trying to express, or whether my insight is invalid. No one has actually presented me with any argument at my level of abstraction that proves me wrong. It appears everyone disects the problem and is able to see what they want to see. However, I see no validity of even discussing the concept of paths when talking about photons. I am claiming that the whole debate about complemenarity is completely irrelevant. Everyone fusses over that when far more interesting is an explanation for what we actually see. As an example, no-one has yet answered the simple question... Why does which-way information appear, even if it is proved to be an illusion? You see it is all very well to say that which-way information is lost, but that does not explain why it is apparently observable. Why do the photons appear to come from one hole or the other? Imagine now that around each hole a cross is marked, and that these crosses are illuminated sufficiently so that the targets reveal not only the photons of the original experiment, but also the holes themselves (marked by the cross). We observe at the target the photons from the experiment and also the image of the cross from their illumination. We seem now to have a problem. We would normally say that photons impacting the targets from the crosses must have at some point hit the cross. Yet for the photons from Afshar's experiement, we have to not believe what we see. Just because we see the photon as coming from one hole, it does not mean that it came from there are all. This is a paradox, clearly. We can't have one rule for some photons and another rule for others. If there is no path information (path is equivalent to which-way) for some photons, there needs to be no path information for any photons. We cannot prove that the photons detected that appear reflected from the crosses ever hit the crosses. Which is actually true. It is impossible to demonstrate, or test. If you can disprove the existance of a path in Afshar's experiment, then that proves what I have been saying all along... there is never a path, for any photons regardless of wires being present or not or the shape of the holes or if there is only one or two holes or whatever else. Dndn1011 16:57, 26 January 2007 (UTC)

I tend to agree with this analysis. One way that Feynamn conceptually describes such experiments is that waveparticls take all possible paths and you sum over these paths to come up with the probability distribution. However, as soon as you measure the position of the waveparticle at some point, path determination for that waveparticle is possible (at least in a mean sense). That's where "which-way" information seems to derive. Trying to track waveparticle paths in between detector and source is another matter because measurement collapses wavefunctions, but it seems to me that if there is ANY interference then there has to be some path available in order for waveparticles to interfere. If you prevent waveparticles from taking certain paths, there is no way that they can take those paths (infinite potential barriers do not permit tunneling, for example). --ScienceApologist 20:22, 26 January 2007 (UTC)

• Sorry to burst your bubbles, but these experiment have been performed and the results do NOT show equal irradiance at the two detectors. -- Prof. Afshar 18:18, 26 January 2007 (UTC)

Dear Afshar, can I have some published reference on these experiments? --Tabish q 18:52, 26 January 2007 (UTC)

• Surely you must be joking. They are very easy experiments to perform, and no expert even worries about publishing about what is clearly available from a simple theoretical calculation. In the course of my experiment I had and my colleagues used these types of experiments to calibrate the setup. BTW-You admit above that your claim is OR, so please remove the related text from the article. If you feel each detector will get 50/50 irradiance even though one pinhole contributes less that the other, then please go ahead and do the experiment, write up your results and submit your paper to a peer-reviewed journal. If you get verifiable results, you would richly deserve a Nobel prize, but let me assure you, you won't! Best regards. P.S. Dear Tabish, let's continue this debate through e-mail, and peer-review process because I will only have time to address you at this point, and have decided not to engage in discussions with non-academics on Wikipedia. Thank you for your understanding and cooperation. -- Prof. Afshar 19:09, 26 January 2007 (UTC)

Dear Afshar, I don't think Noble Prizes are awarded for showing known results of quantum mechanics. I have only claimed what QM tells us. If your wires are too narrow, you won't see this effect, as the dark fringe has to be almost completely blocked to see it. Thanks for the suggestion of doing the experiment - it is not a bad idea at all!
PS: This claim is not part of the article. --Tabish q 19:30, 26 January 2007 (UTC)

I would like to encourage more exchanges of this type. Though a bit off topic, this approximate civility it will encourage more fluid conversations. --ScienceApologist 20:22, 26 January 2007 (UTC)

I do NOT think Afshar should be encouraged to start a response "Surely you must be joking." --Michael C. Price ^talk 21:27, 26 January 2007 (UTC)

And I do NOT think Tabish should be encouraged to start a response "I don't think Noble Prizes are awarded for showing known results of quantum mechanics." But we take what we can get. --ScienceApologist 22:17, 26 January 2007 (UTC)

Tabish's response was generic, Afshar's ad hominem. --Michael C. Price ^talk 22:36, 26 January 2007 (UTC)

OMG, Price, are you going to start arguing about how people argue on this discusion page? Please stop. Now. Dndn1011 22:54, 26 January 2007 (UTC)

Isn't that what you, Linas and SA are doing? :-) --Michael C. Price ^talk 23:12, 26 January 2007 (UTC)

No, there is a difference from saying "Please don't be unpleasant" to arguing over who is most in the wrong which is what you appeared to be doing. Before long we are going to arguing over who had the greatest justification to lay an insult. Now, by all means, lets hear what you have to say shall we? Or shall we just stop, now that I have clarified what I meant? Dndn1011 11:12, 27 January 2007 (UTC)

But was Tabish being unpleasant? Seems to me he was making a perfectly valid point, that there is nothing new about Afshar's experiment -- a point which is frequently overlooked / misunderstood here, despite also being the view of Motl, Unruh et al -- the formalism is obeyed, ergo complementarity (as Bohr understood / defined it) is not violated. And isn't that the crux of the experiment and present debate? --Michael C. Price ^talk 12:30, 27 January 2007 (UTC)

I think that Tabish was being just as unpleasant as Afshar. --ScienceApologist 08:50, 28 January 2007 (UTC)

Guys, I apologize to Tabish and others if I have sounded unpleasant sometimes. It has never been intentional and it's not in my nature to be rude. Please kindly stop this futile thread and move on. Regards. -- Prof. Afshar 19:56, 28 January 2007 (UTC)

I can't speak for Tabish, but I certainly don't think that you deserve any censure for your remarks. I have written things that have been far more unpleasant than that. --ScienceApologist 09:30, 29 January 2007 (UTC)

I add an opinion of working scientist (who has published recently advanced papers both in QFT in brain > QBD, and mathematics > sine-Gordon equation, Informatica 30: 221-232, and a chapter 17 in CRC Handbook of Molecular and Nano Electronics is going to be released spring 2007): YES, for ordinary quantum results no one gives Nobel prizes, YES, Qureshi claims that blocking of all the dark part is needed to see the effect in the unbalanced setup, so according to Afshar setup the increasing of the wire size should not tend to equalize the two images in intensity (although some washing out of the difference between them might be expected), and YES, the which way concept which is bijection is not destroyed by Feynmann's path integral method - in my paper I have used exactly Feynmann's path integral method sum over histories in order to explain the which way concept and the no which way concept. I recommend that the relevant parties do some reading first (but do NOT start with Afshar's papers in order to get a really scientific understanding of what is going on). And last, Afshar's "Original research - OR" complaint is too banal, Qureshi's is thought experiments and is on so basic level that to speak about Nobel Prizes is funny. Noone in 21st century is expecting that playing with lenses and light spots he will get a Nobel Prize. Danko Georgiev MD 05:34, 27 January 2007 (UTC)

Bijections in QM and complementarity

Dear ScienceApologist, below is my reply to your comment that I am oversimplifying the things with bijections, however I will clarify once again the things because you are new to this discussion. However for all others there is no excuse for not reading the sources that I have pointed and there is no excuse that they convert the whole discussion into futile excercise. Well in my wiki-post archived here I describe a 4 slit experiment in two cases [i] different polarization filters on slits A, B, compared to slits C,D, and [ii] a four slit coherent setup. Now in your post you argue that bijections are generally impossible, and I prove this is wrong - everything depends on how you will define the bijection function, and the domain and codomain of the function.

Look the case [i] and the figure. Since the polarization of the photon tells you through which two slits it has passed, then you have the following bijection ${\mathcal {F}}1$

slits A & B -> double slit interference pattern 1 (DSIP1)

slits C & D -> double slit interference pattern 2 (DSIP2)

Domain (two elements only): {{slits A & B},{slits C & D}}

Codomain (two elements only): {DSIP1, DSIP2}

The above bijection function is "which way" function since it established one-to-one correspondence between possible passage through given set of slits, and the probability to hitting the screen, that is the observed intensity of light as distributed on the screen.

Now look at the coherent setup in case [ii] - the "which way" information from the above bijection is erased, you have only one global bijection ${\mathcal {F}}2$ in the form:

slits A,B,C,D -> 4-slit interference pattern

The domain and the codomain contain only 1 element.

Please do seriously consider the possibility that you learn something, and please stop the futile spoiling of the discussion. I have clearly formulated that bijections in QM does not contradict the Feynmann path integral method. Indeed in every setup there is both "which way" and "no which way" information, and this depends on what you have rigorously defined by mathematics.

Example:

Look at the case [i], the bijection function ${\mathcal {F}}1$, if you now look at the single mapping:

slits A & B -> double slit interference pattern 1 (DSIP1),

then you don't have which way information for the photon whether it passed through slit A or slit B, indeed you have "no which way" information for that question, since the photon must pass through both slits!

but YES, you have "which way information" for the question "Which way the photon passed:A,B or C,D?"

Conclusions - escape the popular discussion, and let's do rigorous mathematics. Once one realizes that the term "which way" is itself vacuous without proper definition, he will be able to make some progress and realize where Afshar is wrong. p.s. My example has some connection with the quantification of information. For example let you know that a physical system is in state "A or B". Now how much information you have depends on how you quantify it. If you ask the question "Is the system in state A,B,C,D,E,F,G,H?" you have exaclty 2 bits of information! Yes, you have selected 1 couple of 4 possible couples! But if you ask the question "Is the system in state A or B?" then you have zero bits of information! You really don't know is it in A or B! So please remember this lesson - when you quantify information, the answer depends on the question. The same is in complementarity, the which way information is relative on the question you ask. Regards to everybody in this discussion Danko Georgiev MD 07:01, 29 January 2007 (UTC)

Dear Danko, You are embroiled in the mathematics, but is there not a danger that by doing so you are unable to see the bigger picture? I am not a mathematician, but I can think logically. A true answer must answer all points at all levels. It is not enough to have a proof that works at one level of abstraction only. I am not qualified to assess if your arguments are valid but they do nothing to answer the questions I raise. You appear to be saying "There is which way if you care to think about which way or there isn't if you care to think that there isn't". Sorry but even with my limited grasp of scientific mathematics I knew this already. Please look at the argument I presented for how there is a paradox with the Afshar experiement that can only lead to one conclusion... the concept of which-way (of path) has no validity for a photon. I believe there is a self referential problem with the detailed mathematics somewhere, or the reliance on assumptions. My point which is yet to be countered, is that anything to do with what a photon does between the time of its apparent creation to the time of its apparent detection (and destruction) will always be an assumption. This is in my opinion pointing towards other explanations of the nature of reality. Dndn1011 08:53, 29 January 2007 (UTC)

Dear Danko, I follow you completely up until the point where you declare that this formalism somehow shows that Afshar is "wrong". All of what you discuss is covered in undergraduate quantum mechanics, at the level of the Feynman lectures even. So what, praytell, is your point? You were arguing that scenarios were either 1 to 1 or they weren't. However, if I look at your individual diffraction patters, the probabilities associated with the fringes are decreasing as we head outward from the central fringe. Obviously there isn't a 1 to 1 correspondence within the fringes themselves. You see what happens when you aren't careful with your wording? You end up declaring generalities that do not apply, and wasting kilobytes of space demonstrating ideas that are plainly noncontroversial but also seemingly irrelevant. --ScienceApologist 09:27, 29 January 2007 (UTC)

Sorry, I'm new to this discussion. Can somebody point out which proposed edit to the article is being discussed here, and what verifiable and reliable source it derives from? --Art Carlson 09:23, 29 January 2007 (UTC)

This is not a proposed edit to the article, it is an attempt to describe how "controversial" Afshar's statements really are. Danko is of the opinion that he has demonstrated that Afshar's "results" are bunk. However, what he goes by is his own original research. Right now, said original research is quoted directly in the article. The only reason it hasn't been removed yet is because Danko is basically arguing that it is akin to textbook knowledge that can be confirmed as an elementary thought experiment. However, some of the editors are under the impression that this may not be the case. Hilarity ensues. --ScienceApologist 09:27, 29 January 2007 (UTC)

Thanks. I get the picture. That's the trouble with an article on a topic that is just now reaching the status of a peer-reviewed publication. At best the verifiability of critical appraisal of the idea can be assured, the reliability is already a problem, and peer-review impossible. On the other hand, it seems a shame not to include such a controversy in Wikipedia. I haven't decided whether to enter the fray, but I would like to note that it is not clear in the article whether Afshar is calling into question the methods we use to calculate optics/quantum mechanics, or just the philosophical interpretation of those calculations. It would also be of interest to learn how the optical power is split among detector 1, detector 2, and diffuse scattering for the cases with and without a wire grid. --Art Carlson 10:17, 29 January 2007 (UTC)

Afshar is only questioning the philosophical interpretation of the results of the experiment, the latter which agree with the usual formal calculations (the "formalism"). You are correct: this is not clear from the ghastly mess of the article. --Michael C. Price ^talk 12:08, 29 January 2007 (UTC)

Dear ScienceApologist, I am not futile, nor doing original research! This is basic QM, and basic mathematics, and as was pointed by Prof. Qureshi, noone gives Nobel Prizes for that. All this is on topic because me, Qureshi and Reitzner have mathematically proved, that in Afshar's setup, even without the grid there is NO bijection: slit1 -> detector1, slit2->detector2, so there is NO which way information. Is it clear now? Afshar starts from wrong claim and gives no proof, and then derives a paradox. When me, and Qureshi asked Afshar - where is your proof of the claimed by you bijection, Afshar said "look my new paper". But then see several paragraphs above here - Afshar does not provide the missing proof, but does self-citation in refs 19, 20. Does this clarify why I am not doing OR, and why Afshar is deferring discussion at a very very strating point? Simply for me, Qureshi and Reitzner it is not clear on which fundament the Afshar thesis is built. The which way claim is vacuous, and how you can built science on unproved fact, which you take without any logical necessity. Of course that if you take any wrong thesis without a proof you will end with paradox at the end. Best Regards, Danko Georgiev MD 12:28, 29 January 2007 (UTC)

Actually Afhsar has provided what I will call "proof producing a paradox". A proof that generates a paradox usually means that something is broken... when you are faced with conflicting proofs it must mean that some underlying assumption is incorrect. Afshar has shown this in my opinion, in the statement concerning "conservation of linear momentum". This is basically saying that there should be a 1-1 mapping between hole and detector, because photons take predictable paths through the lens. Additionally I raised with you my example of crosses marked on the holes, so that these crosses are focused on the targets and how claiming that if which way information is not 1-1 mapped to the detector it must mean that no path information (no which way) can exist for any photons anywhere under any cirumstances. You have not actually disproved the "conservation of linear momentum", (unless I missed it, sorry this discussion is getting very messy) and if you were able to you would be in fact agreeing with me, for to disprove it is to say that we can have no true knowledge of the path of a photon (which logically means which-way has no meaning, and thus complementarity is not a useful tool). So I am sorry Danko, but I have to say that you are pushing your own point of view, and I believe you are quite wrong. Not in your mathematics, but in your application of mathematics and the conclusions your draw, which do not appear to me to prove Afhsar wrong at all. You only see as far as trying to preserve the application of complementarity, but you appear to be blind to the consequences of doing so, which ultimately render complementarity inapplicable. I really think you have a logical blind spot here. But more than that, since I stopped taking an active role in editing the article, it has become an absolute mess and, Danko, regardless of who is right about the science, you have not helped the creation of a clear, fair and informative article which despite all these detours into actual physics, is *still* the aim of my own personal contributions are ultimately, and the purpose of this page. You have not clarified things at all, you have merely confused them. Dndn1011 13:50, 29 January 2007 (UTC)