- #1

- 261

- 2

Consider a free particle, say an electron, moving through free space. I have done the calculations, and concluded that the wavepacket must spread -- that is, get wider. However, this does not make sense to me. How can the wavepacket spread with time? That is, why doesn't the wavepacket just translate?

Then I realized that if the wavepacket just translated, we could determine the particle's momentum from its translation.

My questions:

- What does the spreading of the wavepacket with time represent?
- Would spreading appear to both an observer at rest and a non-relativistic observer in motion?
- Why does the "hump" in the packet flatten out as time goes on? (I know the mathematics, but I'm not sure what it represents.)
- Am I right in assuming that the momentum wave function [tex]\phi(k)[/tex] is constant with respect to time?

Thanks for your assistance.