Quantum question - hamiltonian

AI Thread Summary
The discussion revolves around the necessity of a time-independent Hamiltonian in quantum mechanics. One participant questions why the Hamiltonian must be time-independent, arguing that differentiating the expectation value of energy does not require this condition. They also express uncertainty about applying Ehrenfest's theorem to demonstrate the constancy of the expectation value of the Hamiltonian. The conversation highlights the complexities of quantum mechanics and the implications of time dependence in Hamiltonians. Clarification on these points is sought to better understand the underlying principles.
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Homework Statement



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Homework Equations





The Attempt at a Solution



so i don't see why you need H to be time independent..

if you use TDSE to differentiate <Ek| psi> then you get d/dt of that = 0 regardless of whether H is time indep? surely?

Also not sure how to do it using Ehrenfest's theorem. I know that this would show the expectation value of H is constant, but how would this show what is required/// thanks
 

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