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arXiv · 1906.11687

On amplitudes, resonances and the ultraviolet completion of gravity

Rodrigo Alonso·Alfredo Urbano
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Abstract

This letter constructs, making use of the on-shell spinor-helicity formalism, a possible ultraviolet completion of gravity following a "bottom-up" approach. The assumptions of locality, unitarity and causality i) require an infinite tower of resonances with increasing spin and quantized mass, ii) introduce a duality relation among crossed scattering channels, and iii) dress all gravitational amplitudes in the Standard Model with a form factor that closely resembles either the Veneziano or the Virasoro-Shapiro amplitude in string theory. As a consequence of unitarity, the theory predicts leading order deviations from General Relativity in the coupling of gravity to fermions that could be explained if space-time has torsion in addition to curvature.

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Rodrigo Alonso, Alfredo Urbano. 2019-06-27. On amplitudes, resonances and the ultraviolet completion of gravity. https://doi.org/10.1103/physrevd.100.095013

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