Is this right about the double-slit experiment and quantum physics?

ace frehley
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Is this right about the double-slit experiment and quantum physics??

Well I'm trying to understand the double-slit experiment (and quantum mechanics), so could you tell me if this is correct?

A photon is fired through two slits at a plate behind the slits. As long as it isn't observed it takes every possible path from the source (which emits the photons) to the plate. Because of that it interferes with itself creating a interference pattern. But if the photon is observed, the wave function collapses (?) and it is forced to only ''choose'' one path, so a single-slit pattern is formed.

Please tell me if this is correct and what is wrong and why. Any additional information is appreciated.
 
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That is correct. But a few things to keep in mind - first of all, thinking of the photon as taking multiple paths isn't necessarily correct. It's the wavefunction takes those paths. You can't think of it as being a particle at that time. Also, remember that 'observation' is really 'measurement'. It doesn't matter whether this is a conscious observer, or a hidden camera, or a particle detector. The fact is that you interfere with the wavefunction, and trigger a process known as decoherance.
 


Thanks, I'll keep that in mind :)
 
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