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QED’s “All Path Argument” for Mirror Reflection is false, phony, and deceptive.

Discussion in 'Science and Technology' started by Unes, Jun 16, 2017.

  1. Unes

    Unes Active Member
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    QED theory was explained in four lectures by Prof. Richard Feynman at Auckland University in New Zealand. QED's “All Path Argument” is in lecture #2 at about 28:00 minutes of the video #2.



    “All Path Argument” is also explained very clearly in the following short video.



    In order to prove my point that QED’s “All Path Argument” for Mirror Reflection is false, phony, and deceptive, I follow exactly the same steps that it has been demonstrated in this QED presentation, by the end of my presentation, you will see clearly the imbedded flaw in “All Path Argument”, this is like the magician pulled a fast trick on us, and here I am exposing this deception.

    When photons (light) hit to the surface of water at normal (here normal means it is perpendicular to the surface of water, and that makes its angle of incident to be zero) only 2% of photons get reflected, and 98% of photons pass through the surface of water and enter into water. The same situation from the surface of glass reflects 4% of the photons, and the rest pass through the surface and enter into glass. This reflection percentage increases when the angle of incident increases.

    For reflection of light from the surface of water or a glass Science is totally in dark and absolutely has no clue what makes a photon to get reflected, and another photon to pass through. For many years physicists have tried hard to find a property within the photon that would be the cause of this effect, but they could not identify anything in this regard. Finally to handle this phenomenon in practice physicists have developed QED theory (Quantum Electrodynamics Theory), which is based mainly on the statistics that experiments have produced. QED theory in its arguments purely implements the results of the experiments into its well-designed mathematical structures.

    When a photon hits to the surfaces of a glass, the photon gets reflected from both surfaces of the glass. The reflection from both surfaces interacts with each other, and that interaction affects the percentage of the reflection, and it produces strange results. Experiments show that the thickness of the glass plays a major role in the probability of the reflection. QED theory has devised the mathematical tool of amplitude vector to formulate the probability of reflection from both surfaces of the glass.

    QED associates an amplitude vector for each possible path that the photon might get reflected. The length of each amplitude vector is defined purely from the result of the experiment, and it is equal to the square root of the probability that it is revealed by the experiment. This amplitude vector rotates 360 degrees when the photon moves a distance equal to its wavelength. Since there are two surfaces of glass that reflect the photon, then the amplitude vector of the glass reflection is defined by summing up the amplitude vectors from both surfaces of the glass. Here, we need to add one more rule; we have to advance the amplitude vector of the front surface by 180 degree. The probability of the glass reflection is defined by the square of its calculated amplitude vector. Based on this mathematical definition the value of the amplitude vector from each surface of the glass is 0.2, and it depends to the thickness of the glass, the angle between the amplitude vectors from the two surfaces of the glass ranges between 0 and 180 degrees, and this makes the value of the summation of the two amplitude vectors to range between 0.0 and 0.4, and that makes the probability of light reflection from both surfaces of the glass to range between 0.00 and 0.16 (0% and 16%), and this is exactly the result that we get from the experiments. As you see this mathematical structure expresses exactly the result of the experiment, and there is nothing new regarding how light interacts between the two surfaces of the glass.

    QED theory has used the amplitude vector model, and it has tried to explain the optic law of reflection for mirror reflection. The optic law of reflection states that "the incident ray, the reflected ray, and the normal to the surface of the mirror, they all lie in the same plane. Furthermore, the angle of reflection is equal to the angle of incidence". This optic law is correct for each and every one of the photons in the incoming and the reflected images. The consistency of these reflections causes the reflected image to look exactly like the flipped image of the incoming image.

    To explain the mirror reflection with amplitude vector tool, QED has devised "all path argument". QED theory says EVERY photon is reflected from the entire surface of the mirror, and we need to add up all the amplitude vectors from all these paths to get to the final amplitude vector for the photon's reflection. Summing up the amplitude vectors from the entire surface of the mirror shows the amplitude vectors from the edges of the mirror they mostly cancel each other out, only the amplitude vectors from the paths which are close to the path that it is identified by the optic law contribute significant value to the summation of the amplitude vectors. QED's "all path argument" is credited as another evidence in validity and success of the amplitude vector model.

    There are many problems with QED "all path argument", that are explained as follows:

    As I mentioned before in optic law of reflection the direction, the angle of incident, and the normal to the surface of the mirror are crucial in order to define the direction and the angle of reflection. But in QED "all path argument" all of these specific properties of the incoming photons they all have been ignored, so, it does not matter in which direction, and with what angle of incidence, and at which point the incoming photon hits to the surface of the mirror, the summation of the amplitude vectors produces exactly the same result for any of the incoming photons, regardless of all the differences that exist in the incoming photons. Obviously "all path argument" is not satisfying the requirements for the optic law for mirror reflection at all.

    QED's "all path argument" also has no preference for the angle of reflection either! For a SINGLE incoming photon, no matter where you place the receiving photon-multiplier it gets a valid value for the summation of its amplitude vectors. Even if we put multiple photon-multipliers on the receiving side, each one of them does get a valid summation for its related amplitude vectors, and for a SINGLE photon QED's "all path argument" obviously cannot be valid at all. So, QED's "all path argument" generates a summation of amplitude vectors that it does not relate to anything that it is dictated by the optic law for mirror reflection.

    In the presentation of “all path argument”, all the reflected paths are directed toward the photon-multiplier that it is CONVENIETLY placed in the location that it matches with the result from the optic law! So, on its own merit “all path argument” cannot identify the direction of the reflection at all.

    The optic law for mirror reflection is a peculiar phenomenon; it defies all other probabilistic behavior that we have discovered at Quantum level. This strange phenomenon, that it can be observed from the sceneries over the surfaces of calm water, it is revealing something very basic, deep at the fabric of universe, and we needed to reach to the sophistication level of quantum mechanics, in order to realize the extent of its functions.
     
  2. Polymath257

    Polymath257 Thnk & Care
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    There are so many things wrong here that I don't know quite where to begin.

    First of all, reflection and refraction were quite well understood by regarding light as a wave phenomenon. In particular, light is an electro-magnetic wave and the boundary conditions for both the electric and the magnetic fields determine the properties of both reflection and refraction. The double reflection from a layer of glass is also very well understood from the classical description of light as an electro-magnetic wave. This includes effects that depend on the wavelength of the light and are used to *increase* the amount of light passing through a lens, for example (a thin layer of the right material on the lens can allow more light to pass through because of resonance effects--good binoculars have coated lenses for this reason).

    So, you are simply wrong that QED was formulated to explain these effects. They were *all* understood quite well long before QED. In fact, it was well understood long before photons were 'discovered'. This is purely classical science. No quantum mechanics required.

    Now, enter QM. The particle nature of light was shown in the photo-electric effect and explained by Einstein. So now light was described *both* as a wave and as a particle. The question of how the two descriptions related to each other was an important one. What DeBroglie theorized (and others showed) is that every quantum particle has a corresponding wave aspect: electrons, neutrons, photons; *all* quantum particles are also waves! (By the way, the reverse is true also).

    What QED did was to give a fully quantum description of the particle *and* wave nature of light. For classical, macroscopic situations, it reduces to Maxwell's equations and thereby agrees with the classical descriptions of both reflection and refraction. Both are related to the *wave* aspects of light.

    Now, the puzzle of how the particle 'knows' which way to go is common to all quantum particles. Electrons can have many of the same properties as light (which is why we can have electron microscopes) in their wave aspects.

    What the 'all-paths' formulation does is give an *alternative* way of solving the equations of QED. It is fully consistent mathematically with the wave/particle description given previously. And, in some cases, when used properly, it can give insight into the solutions without having to do the detailed calculations.

    Now, your understanding of the 'all-paths' formulation is flawed. The reflection angles observed are a *consequence* of how the amplitudes are added in the all-paths description. The point is that those paths that are not close to the classical paths cancel each other out in this addition and only the 'equal angles' path remains as a major contributor. A similar cancellation happens in refraction also.

    But, and this is important, it is possible to construct situations where that cancellation does not happen and in such cases, the equal angle 'law' no longer works. This happens in diffraction gratings, for example. The light reflected from such is NOT limited to the equal-angle reflection law, but can have different directions of reflection based on the wavelength of the light. Such gratings are used frequently in obtaining spectra and, again, are well-known physical devices.

    \E: Your concerns about *single* photons are common to ALL quantum particles. Remember that quantum mechanics is NOT a causal theory: it is a probabilistic one.
     
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  3. Jayhawker Soule

    Jayhawker Soule <yawn> ignore </yawn>
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    My view exactly, save for the fact that I continue to believe that Lou Malnati's "The Lou" is superb, even more so with anchovies on the side.
     
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  4. Unes

    Unes Active Member
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    Thank you Polymath257,

    I highly appreciate your input. Most of the things that you explained they were in the videos that the links were provided. In this post the subject of my examination is the flaws of all-path argument, and I hope that you narrow your comments on that subject.

    So, QED all-path, this alternative way of solving of QED equation, is this an accepted QED argument? Or it is just a sloppy and inaccurate way addressing the subject of mirror reflection?
     
  5. Polymath257

    Polymath257 Thnk & Care
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    It is a valid way to solve the equations that arise mathematically. As with most physical theories, there is more than one way to approach things, often with very different underlying philosophies, but which are none-the-less equivalent in terms of observation. The all-path methods of QED provide ways of intuiting the solutions which are not provided by with some of the other formulations.

    You make the claim that all photons reflect off the whole surface. This is a misunderstanding. What happens is that in order to figure out the probability of detecting a photon (i.e, the wave function), you add up the contributions of all the amplitudes from all possible paths. Because of the way the amplitudes are evaluated, it turns out that all paths except those close to the classical path cancel out. That means that detection is, by far, the largest for photons on the classical path. Again, this is *all* probabilistic.
     
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  6. Unes

    Unes Active Member
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    Thank you Polymath257,
    I think your explanation verifies that the entire surface of the mirror is participating in the probability of the photon reflection. Actually this is the essence of the all-path argument, and this point has been emphasized in the provided videos. Of course, it is understood well that the amplitude vectors from the paths away from those at the center, they mostly cancel each other out, and their contributions in the summation of the amplitude vectors are very negligible. Besides, why do we bother discussing about the semantics, while the entire argument is formed on baseless foundation!

    Let me give an example that crystallizes one of the flaws that I have described in my opening post. Let us have a photon source at point A, it sends a photon to point B on the surface of the mirror, and the detector receives this photon at point C, as it is stated by the optic law. Now, we sum up the amplitude vectors for all-paths that cover the entire surface of the mirror, and the result of this amplitude summation and the probability matches very closely with the result from the optic law. So far so good!

    Then, I try a second case, I change the direction of the source, in this case the photon still starts from point A, but it hits the mirror at point X, now, let us sum up the amplitude vectors for this case. QED’s all-path amplitude summation process does not differentiate between this case and the first case, and the result of the amplitude summation is exactly the same! But, we do know this is absolutely a wrong result; because detector at point C does detect the photon that started at point A and hit the mirror at point X. This is a vivid example that exposes the flaw within QED’s all-path argument.
     
    #6 Unes, Jun 17, 2017
    Last edited: Jun 17, 2017
  7. Polymath257

    Polymath257 Thnk & Care
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    OK, this is where you have the misunderstanding.

    If we want to figure out the probability of detecting the photon at B that starts at A, we add up the amplitudes of all paths from A to B.

    If we want to figure out the probability of detecting the photon at C that starts at A, we add up all the amplitudes from paths from A to C.

    These are NOT the same collection of paths! In the computations, both the start point *and* the end point are required. All paths between those two points are used for the evaluation of the probabilities.
     
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  8. Unes

    Unes Active Member
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    Thank you Polymath257,

    I am sorry, but there is no misunderstanding or any confusion at all, the issue is crystal clear! QED all-path argument claims: that its method verifies the path of the optic law naturally! This is a false claim. And in this case the path of optic law is from A to B to C. And for the second case the path is from A to X to Y. But QED all-path method cannot distinguish between these two very different paths at all, and its probability can be directed toward any path or multi-path that we choose, and without any constraint.
     
    #8 Unes, Jun 17, 2017
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  9. Polymath257

    Polymath257 Thnk & Care
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    It distinguishes them because the first evaluates all paths from A to C and the second evaluates all paths from A to Y. Both the beginning and the end points are required to do the calculations.
     
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  10. Unes

    Unes Active Member
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    Thank you Polymath257,

    That is exactly one of the points that I covered in my opening post, QED all-path CONVENIENTLY is using the result from the optic law to do its calculation, but on its own merits it has no clue where the path should be. This is like the students DEMAND their professor to provide them with the answer to their puzzle before they attempt to solve their puzzle. And the students claim that they have reached to the right answer, regardless of their crazy methods. And the students also can claim: since they have reached to the right answer, then, that validates their methods. And this is exactly how QED all-path has made its claim.
     
    #10 Unes, Jun 18, 2017
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  11. Polymath257

    Polymath257 Thnk & Care
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    No, the all-paths formulation does *not* need to know a of time what the classical path would be. It *derives* that from the weighted average over all possible paths between the points. You don't need to know the answer ahead of time. Furthermore, when the classical path is *wrong*, for example in a diffraction grating, the all-paths formulation gives the correct answer.

    So, with a single source point, the solution of the standard QED equations would give the wave function for the light from that source. That wave function has a value at every other point in space. What the all-paths formulation does is provide an *alternative* way to evaluate that wave function. It does so by giving the value at any point X by averaging the amplitudes over all paths from the source to X. It turns out that in the case of refraction, the contributions from most paths cancels out and the contribution from paths close to the classical path add up. If you move the point X to a different point, you do the same averaging procedure for all paths from the source to Y and the result is that the classical path to Y is the dominant contribution.

    The clue to which path is relevant has to do with how close by paths add up the amplitudes. Essentially, the length of the path is most relevant to the value of that amplitude. So paths close to the minimal path don't cancel out and those far away do.
     
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  12. Unes

    Unes Active Member
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    Thank you Polymath257,

    In your previous post you mentioned: “
    Both the beginning and the end points are required to do the calculations.”, and now, you have changed your mind and you are saying that those points are *not* required. If the beginning and the end points are *not* required, then in that case as I demonstrated we end up with QED all-path probability method that can be directed toward any path or multi-path that we choose. And we do know this is an unacceptable outcome.

    In this post you mentioned: “
    What the all-paths formulation does is provide an *alternative* way to evaluate that wave function.” Also, you are claiming: “No, the all-paths formulation does *not* need to know a of time what the classical path would be. It *derives* that from the weighted average over all possible paths between the points. You don't need to know the answer ahead of time.If this claim is correct, then the wave function method produces some important information that the all-path method it does *not*. Then how can you say that these two methods are *alternative* of each other!? My hunch is, most likely in the wave function calculation also the result from the optic law have been employed, but you missed recognizing it.

    Also, Prof. Feynman in his lecture he assured his audience that he had been honest in his presentation, and he had not left out anything of importance, except for the mathematical jargon. And in his presentation the path from the optic law was used in the all-path method. As I showed and I am repeating myself, without the optic path, the probability from QED all-path can be directed toward any path or multi-path that we choose, and that conclusion is unacceptable.

    As I showed, the path which it is defined by the optic law is employed to formulate QED all-path method, and nobody caught this mistake.
    And that is a huge mistake, because still the optic law for mirror reflection remains a mysterious PUZZLE, which it defies the QED probabilistic method to its core.
     
    #12 Unes, Jun 19, 2017
    Last edited: Jun 19, 2017
  13. Polymath257

    Polymath257 Thnk & Care
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    The wave function is a function. So, to evaluate it, you need to know the place where it is evaluated. You also need to know the source point since that defines the situation.


    So, the goal is to calculate the wave function that is produces by a source point A.

    You want to evaluate this wave function at the target point X. There are two ways to do this: 1) solve an appropriate PDE. 2) Use the all-paths formulation.

    In the all-paths formulation, you use all paths from A to X to calculate the wave function at X. To calculate the wave function at a different point Y, you use all paths from A to Y.

    If, instead, you solve the PDE, then you get a function. The value at that function at a point X is the same as what you get if you do the all-paths method.

    You do not need to 'direct towards a path'. If you do the all-paths formulation, you can *derive* the classical path. it is NOT assumed ahead of time.



    What 'important information' does the wave function produce that the all-paths formulation does not? In both, the *conclusion* is that the classical path contributes the most to the value of the wave function at a point.


    Clearly, you are not understanding something. If you take any path other than the classical one, paths nearby will cancel out the contribution for your path. This cancellation does not happen for the classical path, That is why the classical path is singled out in the all-paths formulation. it is the path that is NOT canceled.


    This is just a misunderstanding. The optic law is *derived* from the QED not used as an assumption for that technique.
     
  14. Unes

    Unes Active Member
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    Thank you Polymath257,

    Perfect! Let us examine QED wave function model for a photon that it gets reflected by a mirror for the path of the classic optic law from A to X to Y; the path is from source to mirror to detector.

    Our QED wave function model for the photon it starts at point A, and the wave function collapses at point X on the mirror, and the photon gets absorbed by an electron, then, this energized electron is at the state that the direction of its photon emission can ONLY be predicted by a probabilistic model, and that includes many directions, and our desired path from X to Y is just one path among many other possible paths. In this probabilistic model for the emitted photon by the energized electron, the path of the optic law from X to Y, is not privileged. The energized electron emits a photon. This is where the cheating happens, because we implant the target point Y, the correct path, into our QED wave function at point X! So, at point X the wave function that presents the state of the emitted photon, it is already PRIMED to end up at point Y, because as you pointed out: “You want to evaluate this wave function at the target point X”. So, the wave function for the emitted photon at point X does not identify point Y by its own configurations. And as it is expected this wave function ends up at our desired point Y, and it delivers the desired path of X to Y. Without this privileged implementation of point Y into our wave function we would have ended up with ALL the possible probabilistic paths, that QED theory presents for the electron’s emission. This is how we get fooled that QED identifies the path of the classic optic law naturally.

    The classic optic path, which it is the correct path, for the mirror reflection it is also required for QED all-path configuration, because without this guiding path, QED all-path method fails to find the correct path to the detector, in this case, since in all-path the direction and the angle of incident for the incoming photon are all have been ignored, then we are free to choose any path that we like, and each of these paths does produce a calculated summation for its amplitude vectors, which among all of them, only one of them is the correct path, and all the rest are the bogus paths. And QED all-path method cannot differentiate between the correct path and all the bogus paths.

    As you see QED requires the correct answer for the puzzle in advance, both for its wave function calculation, and also for all-path configuration.

    After this revealing conclusion that the path of the optic law is required for the QED all-path configuration, I came to a realization that QED all-path does not claim that it can figure out why the path of the optic law exists, but rather if we use these amplitude vectors for this correct path of optic law, the probability that arises from the summation of the amplitude vectors is in harmony and it is consistent with the path from the optic law. And since QED wave function is *alternate* approach to answer the same problem, then those problems that I raised have been resolved for the most part.

    However, in these QED processes for the path of photon reflection, at point X, what causes the energized electron to emit its photon in the path of the optic law, instead of the general probabilistic pattern still remained unanswered.
    I do appreciate any suggestion on this subject.
     
    #14 Unes, Jun 21, 2017
    Last edited: Jun 21, 2017
  15. Polymath257

    Polymath257 Thnk & Care
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    There are at least two problems here:
    1. The wave function does NOT collapse when the electron absorbs the photon. The wave function only collapses when it is observed. In fact, ALL the electrons have a probability of absorbing the photon and then re-emitting a different photon. Essentially, each and every electron becomes a new source for the E&M wave.. But, because of the difference in the times when the different electrons can be hit by the photon(s) because of different distances from the source, there is a phase shift that occurs. When these different waves from all the electrons are added up, the result produces the reflected wave. For the point Y, the sum of all the contributions from all the electrons cancel out *except* for the contribution that would come from the classical path.

    By the way, the sum of all these contributions is *also* what produces the refracted wave into the material.

    2. No, you do NOT need to know the classical optic path to make these contributions! it simply is NOT one of the inputs into the calculation. In fact, it is one of the *outputs* of the all-paths formulation. But, you have to consider the contributions from *all* the electrons throughout the material and NOT simply the one where the classical path hits the boundary.

    3. (I did say 'at least!') The wave function describes how the reflection happens from the source to ALL points at the same time. Remember that photons are quantum particles and do not have a specific position at any time, nor do they have a well-defined direction *until* they are measured. That measurement is NOT happening at the boundary, so the collapse is NOT at the boundary. It is at whatever locations the final photon is detected. For each such location, the wave function give the probability of detection at that point and from a direction. That can be obtained in another way by looking at the sum of the amplitudes for *all* paths going from the source point and ending at the detection point.
     
  16. Unes

    Unes Active Member
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    Thank you Polymath257,

    The wave function does NOT collapse when the electron absorbs the photon.” This statement is contradictory, because if the photon is actually absorbed by an electron, and even though it was not observed by an observer, then at that situation there is no photon that a wave function could define its state, then the wave function of the incoming photon must had collapsed when it was absorbed, and yet it is claimed that it is not collapsed. This kind of contradictory statement might be arising from the faulty vision that we have implanted into our QED theory. After all if we implanted a faulty configuration, then we should not be surprised getting incoherent outcome.

    I watched the presented video on QED all-path again, they are claiming that the path from the classic optic law is realized naturally by adding the amplitude vectors from entire surface of the mirror.

    I insist this conclusion is based on knowing the path from the optic law in advance, but you are rejecting this notion, and you are insisting that all-path arrives at the path of the optic law by its own devices. Let us put your claim to test, and by not knowing the path from the optic law, you are going to show us that you can figure out the correct path naturally. I suggest the following test.


    I add 99 extra detectors, and label them Y1, Y2, Y3, and so on. Now I calculate the summation of the amplitude vectors for each path that ends to each one of these 100 detectors. Each one of these 100 paths, according to the shown technique, produces a valid probability, and none of these paths is privileged to be special. Now, please show us that your technique will differentiate between these paths and you will recognize the path to detector Y as the correct path.
     
  17. Polymath257

    Polymath257 Thnk & Care
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    Nope. Absorbtion doesn't collapse the wave function. Observation does. All that absorbtion does is *entangle* the wave function.

    Precisely. You don't have to know the classical path ahead of time. It is a consequence of the all-paths formulation.


    Since you have 100 detectors, you have 100 target points. For each one of those targets, you add the amplitudes of all the paths from the source to *that* target. The major contribution to that sum will be from paths close to the classical path from the source to that target.

    Again, all those 100 targets will detect photons eventually. Depending on their placement, they may well have equal probabilities of detecting any given photon.

    When you ask what separates out one particular detector from all the others, you are simply asking about why the wave function collapses as it does. Why one detector picks up a photon and another does not is entirely probabilistic.
     
  18. Unes

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    Thank you Polymath257,

    It sounds that you forgot, we only sent one SINGLE photon to the mirror, and now we are getting 100 photons back!? And then we call QED is incomprehensible!
     
  19. Polymath257

    Polymath257 Thnk & Care
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    In that case, all of the detectors are equally likely to detect it (assuming they are appropriately distributed). Each one is most likely to detect it from the direction of the classical path leading to that detector.
     
  20. Unes

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    +23
    Thank you Polymath257,

    For that SINGLE photon that hits the mirror, we all know how the optic law works, but the task was to show how QED all-path can find the receiving detector without getting any lead from the optic law. Because, QED all-path makes that claim that it finds the path of the optic law by its own method!
     
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