Number of Spin States of a Graviton?
Most recent answer: 07/20/2012
Q:
If spin one bosons have two polarizations like photons, how many polarizations would a spin 2 particle have like a graviton?
- Devon (age 25)
Lansing
- Devon (age 25)
Lansing
A:
Normally, a spin S object will have 2S+1 polarization states. But for massless particles the transverse modes can't exist due to Lorentz invariance. Only the positive and negative helicity states remain. So, the graviton will have only 2 helicity states. The spin 1 photon is an example of this, it also is restricted to its positive and negative helicity states. Although it is straightforward to observe individual photons, I suspect that individual gravitons will never, ever be observed. Their interactions are far too weak.
I tried to find a reasonable explanation for this on the web but was unable to. There are quantum field theoretic ones but they are not for the faint of heart: for example--
LeeH
I tried to find a reasonable explanation for this on the web but was unable to. There are quantum field theoretic ones but they are not for the faint of heart: for example--
LeeH
(published on 07/20/2012)