Low energy photon - electron collision

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Suppose a photon collides with an electron, but does not have enough energy to dislodge the electron or knock the electron into it's next energy level. What happens? Is the effect observed?
 
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Nothing happens. The probability that an electron exists between energy levels is zero, so the probability that it will absorb that level of energy is zero.
 
The photon will scatter off from its initial direction, transferring a little momentum and kinetic energy to the atom as a whole and losing a little bit of energy, thus becoming redshifted. It is like the Compton scattering, only that instead of the mass of a free electron, you should use the mass of the atom.
 
I believe this is what happens in transparent objects
https://www.youtube.com/watch?v=Omr0JNyDBI0
 
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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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