The model-independent approach to quantum gravity: implications of asymptotic flatness

Abstract

The action for the gravitational field in the in-vacuum state is expanded on the basis of nonlocal curvature invariants with arbitrary form factors. It is shown that, for the solution of the expectation-value equations to be asymptotically flat, the form factors should have precisely one-loop behaviour at small ◊. The coefficients of these behaviours measure the rate of the energy radiation through the future null infinity and, at the same time, determine the spectral weights of zero-mass particles in the vacuum. The flux of the vacuum radiation through the future null infinity is calculated to lowest order in the curvature without any assumption about the quantum dynamical model.