- #1
michael879
- 698
- 7
Hi, I'm working with the free space linearized gravitation lagrangian and trying to derive the proper propagator for it. I have no problem doing this, the only problem is that my QFT makes a quick note of what form this should take and I'm off by a factor of 4. The flatspace metric terms matching the components of the contracted graviton fields are of the correct form, and there is a 1/k^2 factor. I'm getting an additional factor of 2 though, while my book has a factor of 1/2. 1/2 makes much more sense to me, since there are two propagator terms, so I feel like I'm doing something wrong. Can anyone confirm what the correct propagator is for me?
*edit* sorry, the lagrangian I am using is the quadratic terms from the weak field expansion of R/kappa
*edit* sorry, the lagrangian I am using is the quadratic terms from the weak field expansion of R/kappa