• Hachem
    384
    The Double Slit Experiment

    It is probably the most important experiment for the credibility of the wave theory of light. But how seriously should it be taken?

    If you look at the different links below and compare them to the images of so-called constructive and destructive interference (you may use this video as a quick introduction), you will see that it is far from being the undeniable proof it is always presented to be.

    In fact, it looks simply like the original image on which a sheet with multiple splits have been laid.

    https://thephilosophyforum.com/discussion/comment/109433
    https://thephilosophyforum.com/discussion/comment/109454
    https://thephilosophyforum.com/discussion/comment/109028
    https://thephilosophyforum.com/discussion/comment/109162
  • Hachem
    384
    Multiple Pinhole Cameras

    If you google this expression, or search it on Youtube, you will find and see many examples of such an original device. I would say that a multiple split grating is something like that. It creates multiple images of the original scene, and that is what we see when we shine a laser beam to such a grating. Through every split a small image of the laser.
  • SophistiCat
    2.2k
    Here is a forum that would better suit your purposes:

    http://www.thescienceforum.com/personal-theories-alternative-ideas/

    Your posts here are off-topic.
  • Mike Adams
    34
    Not necessarily. Proof of an indeterministic universe in which we may be able to exert some agent control is always useful...
  • Banno
    23.4k
    you will see that it is far from being the undeniable proof it is always presented to be.Hachem

    No, I don't see any reason to doubt the standard approach. You will need to present either evidence or an argument.
  • Hachem
    384
    Constructive and Destructive Interference

    1) One of the main arguments in favor of constructive and destructive interference is presented in a very understandable language by the Khan Academy.
    The idea is as simple as it is powerful. Light rays, or rather waves, move towards a point, and for that they travel a different distance according to their start position.
    The difference between two distances determine whether the waves reinforce or negate each other. If the difference is one wave length then we have constructive interference, and by one half-wave length, destructive interference, with all gradations in between.

    2) There is something peculiar about light waves. Unlike water waves whose wavelength play no role in the crossing of a split, as long as the split is high enough, for light waves the height of the split is apparently essential.
    The wave length is defined as the distance between two peaks two troughs.
    Imagine now that the wave has to go through a split as high as the amplitude of the wave, that is the height of the wave. The only obstacle to the wave will be formed by the width of the split since its height is more than sufficient.
    But the width of the wave has, as far as I can see, no relationship with its wavelength.
    For two waves to go at the same time through a split they would have to have a width each at most half that of the split.
    I have not found any indication that the width of the wave played any role in constructive or destructive interference.

    3) Something else. Water waves go up and down, but that has nothing to do with any kind of interference per se. It is a simple matter of gravity. Whatever goes up must come down.
    About two waves colliding with each other. I can certainly imagine that the water will go higher than any of the waves through the collision, just like flying debris when two cars collide, but that's it.
    The whole, mathematical concept of wave is based on the dichotomy peak and trough whereby the first is a positive factor while the second one is negative.
    But a trough, at least as far as water waves are concerned, is, once again, the result of the water coming back down. There is not somehow a movement opposite to the the one creating the peaks. In fact, all the energy goes into creating those peaks, the troughs being more of a secondary phenomenon.

    The mathematical picture of waves may have its uses as far as calculations are concerned, but it certainly does not give a realistic image of reality.

    4) According to the theory, different points, or different waves, go to the same location. Transposed to image formation it would seem that from every point on an object rays are propagated to all points of the image.
    Each point of the image is therefore the final and random result of the combination of an infinite number of rays. Statistically speaking, each image should contain as many cases of constructive as destructive interference, especially if it is a monochromatic image. A red object could therefore never look entirely red.
  • Banno
    23.4k
    Unlike water waves whose wavelength play no role in the crossing of a split, as long as the split is high enough, for light waves the height of the split is apparently essential.Hachem

    What is a split?Did you mean slit?

    I have not found any indication that the width of the wave played any role in constructive or destructive interference.Hachem

    So what? That is, what conclusion do you reach from this?

    The mathematical picture of waves may have its uses as far as calculations are concerned, but it certainly does not give a realistic image of reality.Hachem

    If the mathematics allows us to predict results with great accuracy, then hasn't it ipso facto provided a realistic image of reality?

    Each point of the image is therefore the final and random result of the combination of an infinite number of rays.Hachem

    Not random; and why the switch from waves to rays?
  • Rich
    3.2k
    I have not found any indication that the width of the wave played any role in constructive or destructive interference.Hachem

    Try looking at it using Bohm's version of the Quantum Potential which doesn't move through the slits but rather affects the "particle" by form. It much better, and yes mathematics is all symbolic. It has no relevance to what actually exists because it can't. It only provides some limited predictive measurements.
  • szardosszemagad
    150
    ↪SophistiCat Not necessarily. Proof of an indeterministic universe in which we may be able to exert some agent control is always useful...Mike Adams

    Bit of a self-contradictory wish. If the universe is indeterministic, then the cause-effect chain is ineffective. Control does need cause-effect chain to be working. But it's not. So control is impossible, in a non-deterministic universe.
  • Hachem
    384

    I am afraid I do not share the metaphysics of the Copenhagen school. I do not believe the particle is in anyway affected by mere observation, and I certainly do not believe that it can go through two slits at the same time. This is only considered as possible because of the theory of the dual nature of light.
    That is what I am trying, painstakingly, bit by bit, not to prove, that is I think impossible, but to at least show as plausible.
    This is at the same time an answer to szardosszemagad.
  • Rich
    3.2k
    Bohm's Quantum Potential interpretation is completely different from the Copenhagen Interpretation. The wave is real. The particle is a wave perturbation and is also real. The wave doesn't move but rather the particle is guided by the form of the wave which extends in all directions and acts on the particle non-locally, at a distance. It was Bohm's Interpretation that inspired Bell to develop the Bell's Theorem.
  • Rich
    3.2k
    Bit of a self-contradictory wish. If the universe is indeterministic, then the cause-effect chain is ineffective. Control does need cause-effect chain to be working. But it's not. So control is impossible, in a non-deterministic universe.szardosszemagad

    Choices are constrained and affected by the past memories but are non-deterministic in nature. Because of habits, the universe is probabilistic.
  • Hachem
    384

    I remain firmly deterministic. Call it a metaphysical prejudice.
  • Rich
    3.2k
    I remain firmly deterministic. Call it a metaphysical prejudice.Hachem

    Well, that's your choice.
  • MikeL
    644

    Isn't determinism and probabilistic outcomes two sides of the same coin? It's just where you want to place yourself in time.
  • Hachem
    384

    Let us say that, if there is something like a photon, I am convinced it goes either through one slit or the other.
    https://philpapers.org/post/23274
  • Rich
    3.2k
    Isn't determinism and probabilistic outcomes two sides of the same coin? It's just where you want to place yourself in time.MikeL

    There is a huge difference between trying to place oneself in time (duration) and being placed (the block universe).
  • MikeL
    644
    If I placed myself at the end of time and looked back I would see an indisputable deterministic pattern. If I placed myself halfway through time I have determinism behind me and probability in front of me. In terms of the person watching me walk who is at the end of time, the path has already been set. For me it is being created.
  • Hachem
    384

    I would be inclined to agree with you with the following distinction: there is nothing probabilistic about material processes, only about our knowledge of them and how we react to them.
  • Rich
    3.2k
    When you look back, what you see are blurry memories and possible alternatives you could have chosen but didn't. The memories themselves will be constantly changing and will not be the same as the memory of others. This is not determinism in any fashion.

    Observe what is really happening and not somemodel that some philosophers, or scientists, or science fiction writers have created. Most of what you read are just nice stories. If you are interested in learning about nature then observe it. If you are interested in writing stories and reading imaginative stories, that is fine, but it gets you no closer to understanding nature other than observing the human mind can be quite creative.
  • MikeL
    644
    So you're arguing the constraint of consciousness. Free will. Let me think about that for a while.
  • Rich
    3.2k
    there is nothing probabilistic about material processes,Hachem

    There is no evidence in quantum mechanics or otherwise to support this idea. All evidence is to the contrary. However, one can believe what one wishes to believe.
  • Hachem
    384

    Please remember that this thread is about a light phenomenon, and not about consciousness. That would also be my plea to Rich, not to drown this thread in more general issues, however exciting they may be.
  • MikeL
    644
    No problem Hachem.
    Just let me respond to Rich and I'll drop the subject.

    The memories themselves will be constantly changing and will not be the same as the memory of others.Rich

    So you are arguing that there is no universality to something... I'm rushing a bit. What is it that has no universality? Time?

    If you want to respond in one of my threads (preferably the one nobody has read that would be fine :) )
  • Rich
    3.2k
    So you are arguing that there is no universality to something... I'm rushing a bit. What is it that has no universality? Time?MikeL

    There is duration which is exactly what you are experiencing: memories, possibilities of future actions, choices.
  • Rich
    3.2k
    Please remember that this thread is about a light phenomenon, and not about consciousnessHachem

    They are ultimately intertwined. One cannot understand one without the other. Treating light as a wave or particle gets one no where. The ancients were on the right track. Light is about the spirit.
  • MikeL
    644

    There is duration which is exactly what you are experiencing: memories, possibilities of future actions, choices.Rich

    If you're up for a chat about it come across to The First Few Cognitive Steps Required to Believe in Primordial Soup Theory - I've responded to you there.
  • szardosszemagad
    150
    Bit of a self-contradictory wish. If the universe is indeterministic, then the cause-effect chain is ineffective. Control does need cause-effect chain to be working. But it's not. So control is impossible, in a non-deterministic universe.
    — szardosszemagad

    Choices are constrained and affected by the past memories but are non-deterministic in nature.
    Rich

    Your answer "Choices are constrained... etc." is not a direct response to my observation, furthermore, your answer is full of wishful claims, without any validity to them.

    Your analysis,
    Because of habits, the universe is probabilistic.Rich
    is not at all logical. It is a claim, but it has no merit, due to lack of evidencing or other support. You just make up things as you go, is my opinion.
  • Rich
    3.2k
    Evidence of a probabilistic universe?? How about Quantum Mechanics to begin with? Unfortunately, for determinists, it all ended about 100 years ago. Evidence of choice? We are making them throughout our lives, all the time.
  • szardosszemagad
    150
    Evidence?? How about Quantum Mechanics to begin with? Unfortunately, for determinists, it all ended about 100 years ago.Rich
    If determininsm was false, then the world would be non-causal. If the world were non-causal, then the rules and laws of QM could not be drawn up.

    The rules and laws of QM have been drawn up. You accept they have been.

    Therefore the world is causal.

    Therefore the world is deterministic.

    Your argument I proved wrong.
    ---------------------------------------------------------

    I challenge you to name one, just one rule of QM which is well-known in the public's awareness, and shows that its process is not causal. Thanks.
  • Rich
    3.2k
    If determininsm was false, then the world would be non-causal.szardosszemagad

    Wrong. There are causes but constraints, choices and novelty make the world probabilistic.

    As for turning the QM probabilistic into a deterministic equation, well that is even more strange than determinism itself. Faith dies hard. But, as you wish.
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