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arXiv · 2111.12365

Form Factors in Quantum Gravity - contrasting non-local, ghost-free gravity and Asymptotic Safety

Benjamin Knorr·Chris Ripken·Frank Saueressig
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Abstract

Form factors constitute the key building block when organising the gravitational dynamics in terms of a curvature expansion. They generalise the concept of momentum-dependent couplings to curved spacetime. Moreover, they may capture modifications of the gravitational interactions at high energy scales in a non-perturbative way. We briefly review the role of form factors in various quantum gravity programmes with special emphasis on non-local, ghost-free gravity and asymptotically safe gravity. In this context, we introduce a quantum gravity motivated scalar toy model, which demonstrates that Lorentzian asymptotic safety may be compatible with the causal propagation of gravitons.

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Benjamin Knorr, Chris Ripken, Frank Saueressig. 2021-11-24. Form Factors in Quantum Gravity - contrasting non-local, ghost-free gravity and Asymptotic Safety. https://arxiv.org/abs/2111.12365

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