Bycie sobą

https://www.reddit.com/r/askscience/comments/2qb736/

(...) If the photon reflects off the mirror, it will impart momentum to the mirror. The exact momentum imparted depends on the momentum of the photon, the angle of impact with the mirror, and the angle of reflection.

(...) the photon is in a superposition of all possible paths, implying that it is hitting the mirror at every possible incident angle and is reflecting at every possible angle as well. This places the mirror into a superposition of all possible momentum states from the incident photon. The mirror and the photon have become entangled, in other words.

(...) More specifically, proponents of decoherence attempt to draw a distinction between interactions that preserve phase (coherent interactions), and interactions that lose phase correlations due to entropic phenomena (decoherent interactions). Interaction with the mirror is coherent, interaction with the momentum measuring device, or with some other complex thing such as a human eye, quickly destroys coherence, causing the wavefunction to appear to collapse.

(...) The reason the mirror-photon interaction is coherent is because a good mirror is designed to reflect the incoming light without any interference from thermal agitations of the mirror's atomic lattice. This isn't the case for most measuring devices though.

https://physics.stackexchange.com/questions/368333/

(...) It is not correct that the wavefunction collapses upon interaction. It is "less incorrect" to say that the wavefunction collapses upon detection. "Less incorrect" requires a bit of explanation. (...)

https://copyprogramming.com/howto/when-light-reflects-off-a-mirror-does-the-wave-function-collapse#when-light-reflects-off-a-mirror-does-the-wave-function-collapse

(...) The collapse of the wavefunction upon interaction is not entirely accurate. Instead, it is relatively more accurate to suggest that the wavefunction collapses upon detection. However, this term "less incorrect" requires some elaboration. (...)

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Zadałem sobie to samo pytanie w kontekście odbicia od przesłony między dwoma szczelinami.