A question on Schroedinguer equation

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The discussion centers on the Schrödinger equation and the implications of a large constant N in the context of quantum mechanics. It emphasizes that physical probabilities remain unaffected by N and V_0, with only the average total energy being influenced by these parameters. The reference point of potential energy is deemed arbitrary, allowing any position-independent potential to be incorporated into the wave function as a phase. A substitution of the wave function demonstrates that the modified wave function yields the same physical predictions. Ultimately, the overall phase difference between the wave functions does not alter the underlying physics.
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let be the SE equation in the form:

i\bar\frac{d\psi}{dt}=-\frac{\hbar^{2}}{2m}D^{2}\psi+V(x)\psi+NV_{0}\psi

where N is a big big number N>>1 then what would be the solution?..thanks.
 
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That depends on V(x) doesn't it??
 
eljose,

You will find that physical probabilities are independent of N and V_0. The only thing that will depend on N V_0 is the average total energy. This is a physical consequence of the fact that the reference point of potential energy is arbitrary in quantum mechanics.

This is mathematically evident in that any position independent potential can be absorbed into the wave function as a phase. You can check for yourself that the substitution \psi = e^{-i N V_0 \,t/\hbar} \psi' yields a Schrodinger equation for \psi' given by

<br /> i \hbar \frac{\partial \psi&#039;}{\partial t} = - \frac{\hbar^2}{2 m} \nabla^2 \psi &#039; + V(x) \psi&#039;<br />

However, since \psi and \psi&#039; only differ by an overall phase, albeit a time dependent one, they produce the same physics.
 
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