Main Question or Discussion Point
Question: What would happen if this was delayed even further? We are talking nanoseconds here, but what if the particle was slowed or sent far away, before being reflected back? What I'm getting at is... What if the delay wasn't nanoseconds, but seconds? What if it was minutes? What if it was enough time to manually change whether the second photon was observed or not?http://en.wikipedia.org/wiki/Delayed_choice_quantum_eraser" [Broken]: The results from Kim, et al. have shown that, in fact, observing the second photon's path will determine the particle or wavelike behavior of the first photon at the detector, even if the second photon is not observed until after the first photon arrives at the detector. In other words, the delayed choice to observe or not observe the second photon will change the outcome of an event in the past.
In other words, the photon behaves one way if we observe the second photon nanoseconds later and another way if we don't. So we start the experiment and we observe our detector. Depending on whether we see an interference pattern or not, we observe each secondary photon or we don't and that's the point.The results from Kim, et al. have shown that, in fact, observing the second photon's path will determine the particle or wavelike behavior of the first photon at the detector, even if the second photon is not observed until after the first photon arrives at the detector.
I'm been thinking about this for a while and I can't figure out what would happen. I searched Google and found http://uplink.space.com/showflat.php?Board=sciastro&Number=141733 where someone else asks the same question, but unfortunately no one really seems to understand the experiment, so he gets no real answer.
This is exactly what I'm asking too. Now, depending on how you choose to interpret the delayed choice quantum eraser experiment, there's no getting around that we're either changing the past or predicting the future. So what happens if we delay it long enough to change whether we'll detect or erase the information about the second photon's after observing the results?Now, I turn on my photon generator.. and what do I see? Either a "particle" pattern or an interference pattern, one would presume.
Well, according to the results of the already-performed original "Delayed Choice Quantum Eraser" experiment, what I see depends on what the state of the 'which-path/no which-path' switch will be 10 minutes from now when the idler photon hits it?
What if I see an interference pattern, so then when I see that, I make sure the switch is on "which-path" no matter what... which will clearly violate the results of the previous expirement. I can deliberately violate the rules of what I see on the detector, by switching the switch to what WOULD give me the opposite result, using my own free will.
What is the deal here, and what would happen in this case?
This is not just a theoretical question, this is something that should be possible to test for someone who has access to this kind of equipment, but unfortunately I don't. However, many people have in the past predicted the outcomes of quantum experiments correctly, so I hope someone here can predict the outcome of this experiment as well.
Thank you for your time. :)
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