Can Operators Be Divided in the Schrodinger Equation Derivation?

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SUMMARY

The discussion focuses on the derivation of the Schrödinger equation, specifically addressing the manipulation of operators within the equation. The equation is represented as iħ dU(t)/dt = HU(t), where H is the Hamiltonian and U is the time evolution operator. The user questions the validity of dividing operators and rearranging them, particularly in the context of matrix representations. The solution provided involves using an integrating factor, leading to the conclusion that U(t) = e^{-iHt/ħ} is valid under the assumption that H is time-independent.

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I had a math question about the following steps.

The Shroedinger's equation can be written as follows.

\LARGE i\hbar \frac{d}{dt}U(t) |\psi(0)> = HU(t)|\psi(0)>

Where H is the hamiltonian and U is the time evolution operator.
So U satisfies the Schrödinger equation.

\LARGE i\hbar\frac{d}{dt}U(t) = HU(t)

This is the part that I don't quite understand.

If the hamiltonian H is independent of time, the solution to the above equation is

\LARGE U(t) = e^{-iHt/\hbar}

This is a solution of integration with respect to U to solve for the differential equation.
My problem is that i can't seem to justify the expression:

\LARGE \int i\hbar \frac{dU(t)}{U(t)} = \int Hdt

Am I allowed to divide operators and shuffle them around? Furthermore, when I think of operators in their matrix representation, I am even more confused, since I do not know of matrix division, only inverse operations on matrix.
Any help would be appreciated. Thanks.

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If you're not happy with separating variables you can always use an integrating factor:

<br /> \LARGE \frac{d}{dt}\left(U(t)e^{iHt/{\hbar}}\right) = 0<br />

So then:

<br /> \LARGE U(t)e^{iHt/{\hbar}} = U(0)<br />

U(0) can be normalised to 1 therefore <br /> \LARGE U(t) = e^{-iHt/\hbar} <br />
 

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