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Is anyone aware of a double, double-slit experiment?

Where for example we can see that light and matter display characteristics of both classically defined waves and then classicly defined particles on the second double slit once it is observed from the same source?

So, something like this:

enter image description here

I am curious if the same light source could act as both a wave and a particle, for example, if the third screen displayed particle results after the second double slit once it had been observed. The screens are tagged with the potential results from a typical double-slit experiment.

Joshua G. Edwards
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    Not aware of this no. Seems interesting though. Of course there is the fact that the photons acting as particles will not be the same photons that act like waves. But still interesting – doublefelix Nov 08 '22 at 15:30
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    As after a first slits wave front will be highly dissipated, there will be too small light intensities for a second interference pattern to see, because second double slits acts as some sort of filter. But it may worth a try. – Agnius Vasiliauskas Nov 08 '22 at 15:35
  • @doublefelix interesting I didn't think about that, so it's almost like there are both at the same time and we are just filtering. So we could try to move the observation point to different stages to see if this effects it – Joshua G. Edwards Nov 08 '22 at 16:16
  • Can you explain? You suggest an experiment, but why perform it? What would we learn from it? Are you thinking that slits in screen 2 would affect light differently than how slits in screen 1 affect it? We know what the pattern on screen 2 looks like—just the normal double slit pattern. Are you asking whether the pattern on screen 3 would be different? And, what does the dashed outline labelled "observation" represent? Is that where I am supposed to stand when I look at screen 3 or is it something else? What do you hope to learn from answers to this "question?" – Solomon Slow Nov 08 '22 at 23:01
  • Also, why are screen 1 and screen 2 tagged with "wave result" while screen 3 is tagged, "particle result?" – Solomon Slow Nov 08 '22 at 23:05
  • Hey! @SolomonSlow I was curious if the same light source could act as both a wave and a particle, for example, if the third screen displayed particle results after the second double slit once it had been observed. The screens are tagged with the potential results from a typical double-slit experiment. – Joshua G. Edwards Nov 09 '22 at 17:29
  • Weird my question has been closed, but I haven't been given any feedback, surely the diagram is very clear? – Joshua G. Edwards Nov 09 '22 at 17:37
  • "Closed" is not permanent. Questions can be re-opened, but yours is not as clear as you seem to think. Your picture shows pretty clearly what you want somebody to do, but your reasons for wanting them to do it are what's missing. I did give you some feedback—six questions meant to suggest ways that you could provide more of that "clarity." My key question is, why do you expect the extra slit pair and extra screen to reveal anything different from the original experiment? If you can't explain, then maybe you need to spend some time deepening your understanding of the original experiment. – Solomon Slow Nov 09 '22 at 18:37
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    Joshua, You may want to look at the answers to Multiple Double slit experiment and Sequential Double Double Slit Experiment?. Modifying your question to ask about quantum Double-double slit experiments might be interesting. They were proposed by Nobel Laureate Anton Zeilinger and discussed in papers such as "Quantum double-double-slit experiment with momentum entangled photons" in Nature Scientific Reports. – David Bailey Nov 09 '22 at 19:33
  • @SolomonSlow I've updated as requested, thank you – Joshua G. Edwards Nov 10 '22 at 15:12
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    I have voted to re-open, but I don't have enough rep to re-open the question all by myself. I have an answer ready to post if enough other voters also want to re-open. I suspect that you may be disappointed by my answer though. It's just a more elaborate version of what I've already said: The apparatus consisting of screens 2 and 3 is just a duplicate of the one consisting of screens 1 and 2. The second apparatus won't behave any differently from the first one. You won't learn anything from it that you can't learn from the classic experiment. – Solomon Slow Nov 10 '22 at 15:52
  • I have voted to not re-open. But nevertheless, I think OP might be interested in a infinite-infinite-slit thought experiment posed by Feynman and Hibbs. Suppose that instead of two screens with two slits you had 5 screens with 3 slits. You would still calculate the amplitude at the final viewing screen by adding the contribution from all 243 paths. Now suppose you have 17 screens with 10 slits. You would still calculate the amplitude by adding the contribution from all 100000000000000000 paths... – hft Nov 11 '22 at 23:13
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    Now suppose you fill all of space with screens stacked closely together and then drill holes everywhere in each screen. You would still calculate the amplitude by adding the contribution from all the paths. This is the sum-over-paths approach to quantum mechanics. Very zen. – hft Nov 11 '22 at 23:14

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Multiple diffraction is common in high resolution spectrometers. The waves act like waves all the way through until they reach the detector. It is the detector that performs the "observation": that's where the irreversible dissipative process occurs.

John Doty
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  • Hey! @john-doty, so it is possible that we can observe both and it's actually a flaw in the "observation" stage which causes the difference, so to say? – Joshua G. Edwards Nov 09 '22 at 17:32
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    @JoshuaG.Edwards I don't know what you mean by "flaw". Detectors detect photons, optics manipulate waves. – John Doty Nov 09 '22 at 18:47