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arXiv · 2107.01727

Ultra-Planckian scattering from a QFT for gravity

Bob Holdom
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Abstract

Astonishing cancellations take place in the calculation of high-energy scattering cross sections in quantum quadratic gravity, a quantum field theory for gravity. Tree-level differential cross sections that are minimally inclusive behave as $1/E^2$, as desired for a well-behaved UV completion. Such cross sections are calculated for the various spin states of the massless and massive graviparticles. These describe the hard scattering processes that occur in a picture involving the gravitational analog of parton showers. The structure of some of the simpler amplitudes is also explored. Unitarity without positivity is the key property of the perturbative theory.

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Bob Holdom. 2021-07-04. Ultra-Planckian scattering from a QFT for gravity. https://doi.org/10.1103/physrevd.105.046008

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