One-loop calculations in quantum gravity: graviton self-energy, perturbative gauge invariance and Slavnov-Ward identities

摘要

In this paper we calculate the one-loop graviton self-energy within the framework of causal perturbation theory. Because of this regularization/renormalization scheme, the result is ultraviolet finite, without introducing counterterms, and cut-off-free. In addition, it satisfies the gravitational Slavnov-Ward identities for the two-point connected Green function. The latter are also investigated from the point of view of a perturbative formulation of operator gauge invariance. Then, the condition of perturbative gauge invariance to second order for loop graphs is proved. Corrections to the Newtonian potential coming from the graviton self-energy are also derived. [References: 56]