Waves - bound and unbound states

1. Jul 29, 2009

quasar_4

I was thinking about bound and unbound states the other day and want to know:

Is unboundedness a requirement for a traveling wave? That is, if you were to build a beams from bound states, would they become standing waves?

2. Jul 29, 2009

maverick_starstrider

Well one can decompose a travelling wave solution into an infinite sum of bound states. it's all in the time dependent coefficients.