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arXiv · 1410.7590

Bending of Light in Quantum Gravity

N. E. J. Bjerrum-Bohr·John F. Donoghue·Barry R. Holstein·Ludovic Planté·Pierre Vanhove
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Abstract

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 $\hbar$ contributions. We discuss implications of this computation, in particular the violation of some classical formulations of the equivalence principle.

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N. E. J. Bjerrum-Bohr, John F. Donoghue, Barry R. Holstein, Ludovic Planté, Pierre Vanhove. 2017-04-18. Bending of Light in Quantum Gravity. https://doi.org/10.1103/physrevlett.114.061301

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