I Wave packet experimental detection

VVS2000
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Are there any experimental setups that verify the wave packet dynamics we work with in quantum mechanics?
It just came up in my QM class while we were discussing and even my teachers could'nt figure it out
I know the wave function "collapses" when a measurement is made but still not satisfied with it
 
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Rightfully so. The "collapse" is a very questionable concept and not really needed for the physical interpretation of quantum theory. It's obvious that it depends on the specific measurement made on the measured object, which state this object takes after a measurement has been made. E.g., if you detect a photon in the usual way using the photoelectric effect (e.g., using a CCD cam or a photoplate) this photon gets absorbed and is thus gone for good.

It's of course very difficult to measure "wave-packet dynamics". An example is this:

https://doi.org/10.1103/PhysRevLett.72.3783
https://pure.uva.nl/ws/files/2978244/478_5187y.pdf
 
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VVS2000 said:
I know the wave function "collapses" when a measurement is made
Exactly what "collapse" means depends on which QM intepretation you adopt. Note that discussion of particular interpretations belongs in the interpretations subforum.

In the absence of any particular interpretation, "collapse" is just the mathematical procedure we use to update our model when we know the result of a measurement, and no assertion is made at all about what, if anything, "actually happens".
 
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The "collapse" is simply the update of the state after the interaction with a "filter". This idealized "von Neumann filter measurements" are very rarely achieved. An example is the Stern-Gerlach experiment for measuring and preparing spin states of an atom (in the original experiment silver atoms). Here the atom is send through an inhomogeneous magnetic field. According to quantum mechanics the atom moves in different discrete directions depending on the value of the spin component in direction of the magnetic field. Then the position (or momentum) of the atom is entangled with this value of the spin component, i.e., you can just block all atoms which are at positions referring to the spin value you don't want, and thus all atoms going through this filter have a determined spin component in direction of the magnetic field, and you describe them by a corresponding wave function which is a eigenstate of this spin component with the eigenvalue you filtered out.
 
PeterDonis said:
Exactly what "collapse" means depends on which QM intepretation you adopt. Note that discussion of particular interpretations belongs in the interpretations subforum.

In the absence of any particular interpretation, "collapse" is just the mathematical procedure we use to update our model when we know the result of a measurement, and no assertion is made at all about what, if anything, "actually happens".
yeah I know, that's why I told I was not satisfied with that answer
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
If we release an electron around a positively charged sphere, the initial state of electron is a linear combination of Hydrogen-like states. According to quantum mechanics, evolution of time would not change this initial state because the potential is time independent. However, classically we expect the electron to collide with the sphere. So, it seems that the quantum and classics predict different behaviours!

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