Bending of light in quantum gravity.
We consider the scattering of lightlike matter in the presence of a heavy scalar object (such as the Sun or a Schwarzschild black hole). By treating general relativity as an effective field theory we directly compute the nonanalytic components of the one-loop gravitational amplitude for the scattering of massless scalars or photons from an external massive scalar field. These results allow a semiclassical computation of the bending angle for light rays grazing the Sun, including long-range ℏ contributions. We discuss implications of this computation, in particular, the violation of some classical formulations of the equivalence principle.
Niels Bohr International Academy and Discovery Center, The Niels Bohr Institute, Blegdamsvej 17, DK-2100 Copenhagen Ø, Denmark.
N E J
NE
Bjerrum-Bohr
Department of Physics-LGRT, University of Massachusetts, Amherst, Massachusetts 01003, USA.
John F
JF
Donoghue
Department of Physics-LGRT, University of Massachusetts, Amherst, Massachusetts 01003, USA.
Barry R
BR
Holstein
CEA, DSM, Institut de Physique Théorique, IPhT, CNRS, MPPU, URA2306, Saclay, F-91191 Gif-sur-Yvette, France.
Ludovic
L
Planté
CEA, DSM, Institut de Physique Théorique, IPhT, CNRS, MPPU, URA2306, Saclay, F-91191 Gif-sur-Yvette, France and Institut des Hautes Études Scientifiques, Bures-sur-Yvette, F-91440, France.
Pierre
P
Vanhove