Curvature vacuum correlations in quantum gravity

Abstract

Under the flat Minkowski space-time background,in the harmonic and the arbitrary coordinate systems,we obtained the graviton free propagators in the n-dimensional general relativity (GR) and the high derivative gravity respectively,calculated the expressions of the leading terms of several two-point curvature vacuum correlation functions,and proved that they are zero in the GR,but in the high derivative gravity they are not zero.