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arXiv · 1808.07883

New infra-red enhancements in 4-derivative gravity

Alberto Salvio·Alessandro Strumia·Hardi Veermae
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Abstract

4-derivative gravity provides a renormalizable theory of quantum gravity at the price of introducing a physical ghost, which could admit a sensible positive-energy quantization. To understand its physics, we compute ghost-mediated scatterings among matter particles at tree-level, finding a new power-like infra-red enhancement typical of 4-derivative theories, that we dub '$ghostrahlung$'. Super-Planckian scatterings get downgraded to Planckian by radiating hard gravitons and ghosts, which are weakly coupled and carry away the energy.

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Alberto Salvio, Alessandro Strumia, Hardi Veermae. 2018-08-23. New infra-red enhancements in 4-derivative gravity. https://doi.org/10.1140/epjc%2Fs10052-018-6311-1

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