Uncovering the Mystery of Photon Wavelength Reflection and Momentum Transfer"

[Neo_Anderson]

...become longer in its wavelength after it reflects off something? After all, photons do have momentum; I'd at least expect photons to transfer some of its energy to the object as it reflects off it, causing them to become less energetic, hence lengthening its wavelength.
I'm mistaken, I know, but how so?...

 

[jtbell]

You're not mistaken. However, try calculating how big this effect would be in a practical situation, and you'll probably get an idea of why people don't talk about it much.

 

[Matterwave]

Compton scattering is a very analogous phenomenon to the one you are describing.

 

[jtbell]

Sure, if a photon scatters off an individual electron or other elementary particle (Compton scattering is an example), or probably even an atom, the change in wavelength is noticeable. I had the impression Neo was thinking of macroscopic objects (maybe I was mistaken).