What is the Inverse of Momentum Operator in One Dimensional Problems?

ghazal-sh
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hi every body!
I'm looking for inverse of momentum operator in one dimensional problem.I have no idea to solve it!please help me!
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so sorry about my bad speaking!
 
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Welcome to PF!

ghazal-sh said:
hi every body!
I'm looking for inverse of momentum operator in one dimensional problem.I have no idea to solve it!please help me!

hi ghazal-sh! Welcome to PF! :smile:

Thankyou for the PM.

Can you show us the whole problem? :smile:
 
Can you show us the whole problem?
thanks for your attention!::smile:
the problem is just finding inverse of P!
 
Start by considering the action of the momentum operator P on an arbitrary wavefunction \psi(x)...What is that?
 
Start by considering the action of the momentum operator LaTeX Code: P on an arbitrary wavefunction LaTeX Code: \\psi(x) ...What is that?
thanks!how can you reach to 1/p with this approach?
of course I found the answer.start by calculating expectation value of 1/p in momentum space (so easy)and then use Fourier transform of the wave functions.after so simple calculation you can see that:1/p =integral of dx
 
Last edited:
ghazal-sh said:
thanks!how can you reach to 1/p with this approach?
of course I found the answer.start by calculating expectation value of 1/p in momentum space (so easy)and then use Fourier transform of the wave functions.after so simple calculation you can see that:1/p =integral of dx

Well, the action of P on \psi(x) is of course just P\psi(x)=-i\hbar \frac{d}{dx} \psi(x)...what do you get when you multiply both sides of this equation by the inverse of P (from the left), P^{-1}?... compare that to the fundamental theorem of calculus and it should be apparent what P^{-1} is.

P.S. using 1/p to represent the inverse is usually bad notation when dealing with operators.
 
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