# Integrate Laplacian operator by parts

Tags:
1. Jan 18, 2016

### Eric_J

This is the key step to transform from position space Schrodinger equation to its counterpart in momentum space.
How is the first equation transformed into 3.21?
To be more specific, how to integral Laplacian term by parts?

Last edited: Jan 18, 2016
2. Jan 18, 2016

### dextercioby

Do you know tensor tensor calculus or at least the Gauss-Ostrograski theorem in 3D?

3. Jan 18, 2016

### Eric_J

Thanks for the hint!