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arXiv · 2105.04566

Non-perturbative propagators in quantum gravity

Benjamin Knorr·Marc Schiffer
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Abstract

We employ non-perturbative renormalisation group methods to compute the full momentum dependence of propagators in quantum gravity in general dimensions. We disentangle all different graviton and Faddeev-Popov ghost modes and find qualitative differences in the momentum dependence of their propagators. This allows us to reconstruct the form factors quadratic in curvature from first principles, which enter physical observables like scattering cross sections. The results are qualitatively stable under variations of the gauge fixing choice.

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Benjamin Knorr, Marc Schiffer. 2021-05-10. Non-perturbative propagators in quantum gravity. https://arxiv.org/abs/2105.04566

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