I know when the initial state ($\Psi (x,0)$) is given, $\frac{d\langle x\rangle}{dt} \not= $ $\langle p\rangle$. I thought you can only apply Ehrenfest's theorem when $\Psi$ is a function of $x$ and $t$, however it seems like you can also apply it to the time-independent part ($\psi (x)$) by itself as well. Can someone explain to me why Ehrenfest's theorem is valid for $\psi (x)$, and or why it is not valid for $\Psi (x,0)$. This is my first time posting, not sure how the latex coding will look.

Thanks!