I Double Slit Experiment: Measurement versus Observation

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The discussion centers on the double slit experiment and the implications of measurement versus observation in quantum mechanics. It explores whether the experiment has been conducted with equipment to monitor which slit a particle passes through while ensuring the data is destroyed before human observation. It concludes that the presence of which-path information, even without human detection, prevents the formation of an interference pattern. The concept of "observation" in quantum theory is clarified, emphasizing that interaction with a measuring device, rather than human awareness, determines the outcome. Overall, the conversation highlights the intricate relationship between measurement, data, and quantum behavior.
Praxiteles
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Measurement versus Observation
I'm curious if the double slit experiment has ever been done where the equipment is in place and enable to monitor which slit the particle goes through, but the data is destroyed before anyone ever sees it.
 
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Praxiteles said:
TL;DR Summary: Measurement versus Observation

I'm curious if the double slit experiment has ever been done where the equipment is in place and enable to monitor which slit the particle goes through, but the data is destroyed before anyone ever sees it.
It may have happened by accident!
 
Praxiteles said:
TL;DR Summary: Measurement versus Observation

I'm curious if the double slit experiment has ever been done where the equipment is in place and enable to monitor which slit the particle goes through, but the data is destroyed before anyone ever sees it.
Depending on your exact definition of "data is destroyed before anyone ever sees it": The answer is yes. If the which slit information is present in the system, but without there being any detection mechanism whatsoever, then you see no interference pattern. The mere possibility of obtaining that information is enough to eliminate that. In the following experiment, which-path markers are placed on photons on the way to a screen. See figure 9, no DS interference. They then "erase" the marker, which then restores the interference pattern. See figure 10.

Young's double-slit experiment with single photons and quantum eraser

No human knowledge is required, because no human ever possesses any.
 
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You may have a misconception about what "observation" means in quantum theory. It means that the wave in question has interacted with something to give a result. Whether a human observed the interaction or result is irrelevant to the quantum theory.
 
We often see discussions about what QM and QFT mean, but hardly anything on just how fundamental they are to much of physics. To rectify that, see the following; https://www.cambridge.org/engage/api-gateway/coe/assets/orp/resource/item/66a6a6005101a2ffa86cdd48/original/a-derivation-of-maxwell-s-equations-from-first-principles.pdf 'Somewhat magically, if one then applies local gauge invariance to the Dirac Lagrangian, a field appears, and from this field it is possible to derive Maxwell’s...