Why is a time-dependent Hamiltonian different in quantum mechanics?

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In classical mechanics, if there's an explicit time dependence in the Hamiltonian of a system, then it won't be equal to the system's total energy. Why isn't this true in quantum mechanics?
 
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In classical mechanics, if there's an explicit time dependence in the Hamiltonian of a system, then it won't be equal to the system's total energy.
Can you show an example of this?

If the time-dependence in the Hamiltonian is just some external potential, it should be fine. And I do not see how you get different time-dependent expressions in quantum mechanics - the particles and fundamental interactions have to stay the same.
 
mfb said:
Can you show an example of this?

No, I can't. I just confused myself. Thanks.
 

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