Doppler Shift of Waves

Most recent answer: 02/21/2016

Q:
Doppler shift of light and sound waves is well established phenomena.Is it applicable to De Brogile's matter waves? I would like to have answer with some good references.
- Har Sukhdeep Singh (age 63)
Delhi,India
A:

Sure, the reason for the Doppler shift has nothing to do with the detailed type of wave. Look at it this way. Think of a wave representing massive particles (say electrons) coming toward you with some momentum and energy. For quantum waves the energy is proportional to the frequency. If you now start moving toward the source of the wave, in your new reference frame the frequency is higher, for exactly the same reason as for any other wave. So the energy is higher in the new frame. The rest energy is the same, so that tells you the momentum is also larger in the new frame. That's just like the classical result, since in the new frame the particles are moving faster than in the old frame. Pretty much any introductory quantum text will describe all this.

Mike W.


(published on 02/21/2016)