What does the delayed choice quantum eraser experiment prove?

Discussion in 'Physics & Math' started by Pious, May 3, 2014.

  1. Pious Registered Senior Member

    Messages:
    29
    In the delayed choice quantum eraser experiment, our conscious observation affects the creation of not only the present, but also the "past" of the electron.

    Does it prove there was no physical reality in the past at the slits, prior to the pulling away of the film for our conscious observation to happen? Does it prove there can actually be no matter, space and time independent of conscious observers? Why or why not?
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. Farsight

    Messages:
    3,473
    It doesn't prove anything. Find an article on it, and try to really understand it. For example, see wikipedia and note this:

    "Some have interpreted this result to mean that the delayed choice to observe or not observe the path of the idler photon changes the outcome of an event in the past. However, the consensus contemporary position is that retrocausality is not necessary to explain the phenomenon of delayed choice".

    It's "quantum woo", akin to mysticism. I'm afraid popscience articles are full of this sort of thing. Woo sells magazines. Some dull boring explanation that explains why it isn't magical and mysterious doesn't. Quantum physics has got nothing to do with conscious observers, despite what you've heard. Schrodinger proposed his cat to demonstrate how ridiculous all that stuff was, but it's been hijacked by the woo-peddlers.
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. Pious Registered Senior Member

    Messages:
    29
    Wikipedia is a poor source, this article you are reading from seems to be written by dogmatics and ignorant materialists, just as you seem to be. But I am not interested in what some ignorant people say. I am interested in the opinion of serious physicists.

    Please understand the actual experiment before discussing. This video may help you.

    [video=youtube;H6HLjpj4Nt4]http://www.youtube.com/watch?v=H6HLjpj4Nt4[/video]

    So the question arises, does this experiment prove that "past" is not fixed if not registered in our knowledge in the present?
     
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. Farsight

    Messages:
    3,473
    No this experiment does not. And I do understand it.

    But what more can I say? If you want to believe in magick and mysticism and rewriting history whilst dismissing people as "ignorant materialists", that's your choice, Pious.
     
  8. rakovsky Registered Member

    Messages:
    56
    Why not? What other possibility is there?

    I have difficulty understanding these issues, but it looks to me like retrocausality is the best explanation:

    Please Register or Log in to view the hidden image!




    The issue is not necessarily that "Woo sells", but that "discovering something new sells."
    When Vasco De Gama's voyage discovered the mid-Pacific and proved with finality for everyone that the earth was round, it was big news, not because the Round Earth theory is woo, but because it's a new discovery or new, final proof.

    Archimedes also had a famous non-woo Eureka moment, didn't he?
     
    danshawen likes this.
  9. rakovsky Registered Member

    Messages:
    56
    What do you mean by magick vs magic?
    Just an alternate spelling?
     
  10. rakovsky Registered Member

    Messages:
    56
    It's an interesting question. I discussed an experiment involving delayed choice and retrocausality on message #58 in my thread here:
    http://www.sciforums.com/threads/ho...and-how-do-we-know.158973/page-3#post-3450078

    Did you consider that there could be multiple realities preceding the pulling away of the firm?
    There is a theory in science that an electron or quantum particle exists in every state at any given moment in time, isn't there?
    So,
    one might not even need to go into discussions of the past to ask this question.
    One can ask: How can it be that the particle, according to science, exists in more than one state at one time, and that at the moment of observation it shows only one state?
     
  11. danshawen Valued Senior Member

    Messages:
    3,942
    Choosing a slit to observe means choosing a direction. No surprises there.

    It actually takes another charge in the vicinity to accelerate an electron so it produces a photon. In hydrogen, this would be a proton, but for the photons emitted from most atoms, the other charge that has the most influence in the emission of a photon is going to be an ENTANGLED electron.

    According to Special Relativity, no two events separated by light travel time are ever simultaneous, but quantum spin flips are, and quantum spin flips are exactly what you are observing with the double slit.

    If instead of a double slit, you could observe entangled spin flips in a single atom emitting a photon, which of the simultaneous spin flips would appear to occur first? The one that is closer to you, or the one further away? It would depend on the DIRECTION the observer approached those events, wouldn't it?

    The double slit simply changes the angle of the observation to a smaller slice of the orbital electrons. The flips happen faster than the propagation of light between the electrons, AND AT ANY ANGLE OF SEPARATION OF THE PAIRED ELECTRONS. Now the double slit has taught you something about entanglement that is hard to believe; that for all intents and purposes, those entangled electrons, and under certain conditions, the entangled photons they produce, are traveling much faster than the speed of light in a vacuum. Draw your own extended conclusions.
     
  12. Richard Townsend Registered Member

    Messages:
    3
    I don't think anyone understands it. There are various interpretations but none of these can be tested.

    The problem is as soon as you come up with a tenable theory it raises further questions, which takes us further down the rabbit hole. We may never really understand these things because there are limits to what we can know.
     

Share This Page