1. Sep 21, 2004

theFuture

So in my problem set I'm asked to solve for the "new energies of the system" I'm given the initial energies of this system and told a new potential is added. I know all the matrix elements. I solved for H|psi> so where do I go from here for the energies?

2. Sep 21, 2004

sinyud

I'm not sure, but can't you just solve H|psi> = E |psi> for the new Hamiltonian which is defined by

H=-hbar^2/2m Laplacian +Vold+Vnew

3. Sep 21, 2004

theFuture

That's what I was thinking but I was curious if there was some other trick buried in the Dirac stuff. Thanks.

4. Sep 22, 2004

Kane O'Donnell

The lecturer might be asking you to use pertubation theory - is the new potential small compared to the old?

Kane

5. Sep 22, 2004

humanino

I think Kane is right.

You can check wikipedia about the Dirac notation.