Generalized Schrödinger equation

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The discussion revolves around the Generalized Schrödinger equation and the treatment of the exponential term e^(-iEt) in relation to the coefficients of eigenvectors in wave functions. Participants clarify that while e^(-iEt) is indeed time-dependent, it can be conflated into the notation for alpha, simplifying the expression. The confusion arises from whether this exponential should be treated as a constant or a variable in the context of differentiation. The consensus is that the exponential captures the time dependence of alpha, and thus its treatment is valid within the equation. Overall, the conversation emphasizes understanding the role of time dependence in quantum mechanics equations.
Maximise24
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This equation (see attachment) appears in one of Prof. Susskinds's lectures on Quantum Mechanics: in trying to differentiate the coefficients of the eigenvectors of a wave function with respect to time, an exponential e^(-iEt) is introduced for alpha.

I can see that d/dt e^(-iEt) = -iE e^(-iEt), but why is the second part e^(-iEt) not in the top equation in the attachment? Is it disregarded because it's just a number?

Thanks for any help provided!
 
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But the exponential is there, disguised under the form of 'alpha' in the rhs.
 
OK, so \alphaj(0)e-iEt has simply been conflated into \alphaj? Can you just do that since e-iEt is not a constant?
Thanks!
 
The only variable is time. e^{-iEt} in units with hbar=1 gathers the time dependence of alpha.
 
Maximise24 said:
OK, so \alphaj(0)e-iEt has simply been conflated into \alphaj? Can you just do that since e-iEt is not a constant?
Thanks!

Aj is defined on the second line of your picture. It doesn't look like a constant to me.:smile:
 
OK, thanks guys.