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arXiv · 2002.02459

Universality in the classical limit of massless gravitational scattering

Zvi Bern·Harald Ita·Julio Parra-Martinez·Michael S. Ruf
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Abstract

We demonstrate the universality of the gravitational classical deflection angle of massless particles through O(G^3) by studying the high-energy limit of full two-loop four-graviton scattering amplitudes in pure Einstein gravity as well as N >= 4 supergravity. As a by-product, our first-principles calculation provides a direct confirmation of the massless deflection angle in Einstein gravity proposed long ago by Amati, Ciafaloni and Veneziano, and is inconsistent with a recently proposed alternative.

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Zvi Bern, Harald Ita, Julio Parra-Martinez, Michael S. Ruf. 2020-02-06. Universality in the classical limit of massless gravitational scattering. https://doi.org/10.1103/physrevlett.125.031601

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