Using a coordinate-independent impact parameter in the post-post-Newtonian light deflection formulas

Abstract

In [2] we have seen that among the post-post-Newtonian terms in the light deflection formulas there are "enhanced" ones that may become much larger than the other post-post-Newtonian terms. It is demonstrated here that these "enhanced" terms result from an inadequate choice of the impact parameter. Introducing another impact parameter, that can be considered as coordinate-independent, we demonstrate that all "enhanced" terms disappear from the formulas.