# Quick question about integrating limits in QM problems

1. Dec 5, 2014

### rwooduk

Am I correct in assuming that if there is a potential present and it is not infinite then integrals will always be made from minus infinity to infinity, but where an infinite potential exists then the integral will depend on the size of the confinement area?

Sorry to be a little disambiguous, it's for no particluar question, just trying to clarify the limits of integration for general QM problems.

Thanks for any thoughts.

2. Dec 5, 2014

### Orodruin

Staff Emeritus
Technically you could consider the integration bounds to always be from minus infinity to plus infinity, but that the wave function is zero where the potential is infinite and thus it is equivalent to an integral over the region where the potential is finite.

3. Dec 5, 2014

### rwooduk

I like this! Thanks very much for the reply!