Deriving the needed wavefunction transformation for gauge symmetry?

quarky2001
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Homework Statement


Take the Schrodinger equation for a point particle in a field:

i\hbar \frac{\partial \Psi}{\partial t} = \frac{1}{2m}(-i\hbar\nabla - q\vec{A})^2\Psi + q\phi\Psi

I'm supposed to determine what the transformation for Psi is that corresponds to the gauge transformation A\rightarrow A +\nabla F and \phi \rightarrow \phi - \frac{\partial F}{\partial t}

The Attempt at a Solution



I know what the transformation should be, since these transformations are actually derived the other way around in most textbooks, but I have no idea how to work from these transformations to get the necessary operator for \Psi \rightarrow \Psi\prime.
 
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Assume you have a function psi that satisfies the Schrodinger equation with the un-transformed A, phi, then ask what psi' needs to be to satisfy the Schrodinger equation with the transformed A', phi'.
 
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