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Thread: Independent Variable of Two Slit Experiment

  1. #1 Independent Variable of Two Slit Experiment 
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    I have read several descriptions of the famous Two Slit Experiment. The first time, the pattern created by the light is that of a wave, but the second time, the pattern created is that of a particle. What I don't understand is what you change between the two. I know it has something to do with a human observer, but I never understood exactly what. Is having a person in the room enough, or does he have to look at the film as it changes? Also, during the first test, why does the film not enter a superstate after exposure and then collapse to show one pattern when you look at it?

    For the record, I am not trying to disprove quantum theory. I just don't understand how this experiment works. Thank you for the answers in advance.


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    Quote Originally Posted by Jewish-Scientist View Post
    I have read several descriptions of the famous Two Slit Experiment. The first time, the pattern created by the light is that of a wave, but the second time, the pattern created is that of a particle. What I don't understand is what you change between the two. I know it has something to do with a human observer, but I never understood exactly what. Is having a person in the room enough, or does he have to look at the film as it changes? Also, during the first test, why does the film not enter a superstate after exposure and then collapse to show one pattern when you look at it?

    For the record, I am not trying to disprove quantum theory. I just don't understand how this experiment works. Thank you for the answers in advance.
    A reasonably good summary is the wiki article: Double-slit experiment - Wikipedia, the free encyclopedia

    As you'll read, it's not the presence or absence of a human observer that matters. It's where the detector is placed, and what it's designed to measure. Many pop-sci articles try to add layers of woo by invoking "the observer effect" and then moving on to consciousness and thence to full-on new-age crackpottery. Just ignore that noise. There's enough real mystery without inventing some.


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  4. #3  
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    So how light is measured decides what light is, right?
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    Anti-Crank AlexG's Avatar
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    Not what it is, but what aspect of it is observed.
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    Its the way nature is!
    If you dont like it, go somewhere else....
    To another universe, where the rules are simpler
    Philosophically more pleasing, more psychologically easy
    Prof Richard Feynman (1979) .....

    Das ist nicht nur nicht richtig, es ist nicht einmal falsch!"
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    The example that I was always given with the Uncertainty Principle is with the velocity and position of a particle, but does it also ably here? Something along the lines of, "if we measure light as a wave, then we can not measure it as a particle" and vice verse.
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    Quote Originally Posted by Jewish-Scientist View Post
    The example that I was always given with the Uncertainty Principle is with the velocity and position of a particle, but does it also ably here? Something along the lines of, "if we measure light as a wave, then we can not measure it as a particle" and vice verse.
    Something like that, yes. If you set up a detector to determine precisely which slit the electrons (say) go through, the interference pattern (essentially representing the momentum) disappears. Thus one may regard the uncertainty principle as an "explanation" of the double-slit experiment, as you suggest. This interpretation often triggers a round of discussion about what constitutes an "explanation," and whether there is a "better" one, and so on, as most (perhaps all) explanations do (or should). But at minimum, we can certainly say that the experimental outcomes are consonant with expectations derived from the uncertainty principle.
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    Thanks. I think I understand the experiment now.
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  9. #8  
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    Technically, what determines whether or not one has a double-slit interference pattern is whether the two quantum states corresponding to the photon passing through one or the other slit is orthogonal when the photon is measured. If the two states are not orthogonal, there will be a double-slit interference pattern, and if they are orthogonal, there will be no double-slit interference pattern because orthogonal states cannot interfere (due to Pythagoras' theorem in the Hilbert space). One way that these two states can be made orthogonal is to rotate the plane of polarisation of the photon passing through one of the slits by 90. Another way is to measure which slit the photon passed though. When any observable is measured, the states corresponding to each of the possible results are orthogonal. It doesn't matter how the measurement is performed, whether directly or indirectly on a quantum entangled partner.
    There are no paradoxes in relativity, just people's misunderstandings of it.
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    As an ether theorist I believe KJW's approach based on procedural changes in magnetic polarities within the double slit setup is important but misses the key which is how such alterations (adding monitoring devices on the sides or the like) would affect the etheric processes which in turn determine what is oberved at our quantal level of observation. -To give the basic theory of how an ether model would accxount for the apparent particle-wave duality would be lengthy but I'll try encapsulating it: transmission of observable (quantal scale) light is connected resonationally with simultaneous transmission at the etheric level, and the two are constantly in resonance with each other. When we follow a "particle of light" or photon, we are actually seeing a particle-capacity energic unit composed of elemental etheric units. (All energic resonances occur at the elemental etheric level. That's what makes for a uniform, orderly pattern of energic resonance transmission throughout the universe.) When we perform the double slit, we think we're tracking a single "solid" particle through "empty space" but that's all due to a false basis in theory based on Einsteinian general relativity and quantum mechanics, both of which need to be discarded. -What we're actually observing is the track of a quantal scale energic unit (photon) composed of elemental etheric units passing through a "sea" of smaller and smaller resonational units. The smallest are the elemental etheric units, then next up the size scale, etheroidal (still undetectable to our quantal scale observation) units, and finally the observable units, the subatomic and atomic scale units. These are all in resonation with each other, such that there is a cross-over between observable subatomic and atomic units and the more numerous sea of etheroidal and etheric units, so that the photon, as it is transmitted, simultaneously "sets off" resonant "waves" at the etheric level, some of which resonate back "up" the scale to the atomic level and are seen as "waves." (I have given a more detailed model of how a universal ether resonant at the elemental level would have arisen from pure space, elsewhere in this Forum, over the last couple months.)
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    Brassica oleracea Strange's Avatar
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    Quote Originally Posted by Michael Anteski View Post
    As an ether theorist
    A.K.A. "idoit"

    I believe KJW's approach based on procedural changes in magnetic polarities
    No one mentioned "magnetic polarities". You either can't read or know nothing about science. Or both.

    how such alterations (adding monitoring devices on the sides or the like) would affect the etheric processes
    There is no evidence of "etheric processes". You refuse to discuss any evidence, so why keep bringing this up?

    which in turn determine what is oberved at our quantal level of observation.
    Quantal is still not a word, however often you keep using it.

    -To give the basic theory of how an ether model would accxount for the apparent particle-wave duality would be lengthy
    It would be mathematical and use evidence. Either requirement rules out your "theory".

    <drivel deleted>
    Please refrain from posting this nonsense in serious discussions about science. There is a Trash forum specifically for people like you.
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    [QUOTE=Strange;447890]
    Quote Originally Posted by Michael Anteski View Post
    which in turn determine what is oberved at our quantal level of observation.
    Quantal is still not a word, however often you keep using it.
    It's an Australian airline isn't it?
    "[Dywyddyr] makes a grumpy bastard like me seem like a happy go lucky scamp" - PhDemon
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    Quote Originally Posted by Michael Anteski View Post
    As an ether theorist I believe KJW's approach based on procedural changes in magnetic polarities within the double slit setup is important but misses the key which is how such alterations (adding monitoring devices on the sides or the like) would affect the etheric processes which in turn determine what is oberved at our quantal level of observation. -To give the basic theory of how an ether model would accxount for the apparent particle-wave duality would be lengthy but I'll try encapsulating it: transmission of observable (quantal scale) light is connected resonationally ...blah blah blah
    It's interesting how many crackpots eschew the multiple paragraph.

    The random use of words like "resonance" and the invention of pseudoscientific terms "energic, etheric and quantal", supplemented here with totally made-up resonation and etheroidal are sure signs of a self-deluded crackpot. Please, as Strange suggests, confine your nonsense to the Trash. Stop polluting the forum with your sci-fi fantasies. Some folks here actually want to talk about science.

    Grazie.
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  14. #13  
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    [QUOTE=Dywyddyr;447891]
    Quote Originally Posted by Strange View Post
    Quote Originally Posted by Michael Anteski View Post
    which in turn determine what is oberved at our quantal level of observation.
    Quantal is still not a word, however often you keep using it.
    It's an Australian airline isn't it?
    "I hate quantal..."
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