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arXiv · 1901.01731

Scales and hierachies in asymptotically safe quantum gravity: a review

Frank Saueressig·Giulia Gubitosi·Chris Ripken
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Abstract

The asymptotic safety program strives for a consistent description of gravity as a non-perturbatively renormalizable quantum field theory. In this framework the gravitational interactions are encoded in a renormalization group flow connecting the quantum gravity regime at trans-Planckian scales to observable low-energy physics. Our proceedings reviews the key elements underlying the predictive power of the construction and summarizes the state-of-the-art in determining its free parameters. The explicit construction of a realistic renormalization group trajectory describing our world shows that the flow dynamically generates two scales: the Planck scale where Newton's coupling becomes constant and a terrestrial scale where the cosmological constant freezes out. We also review the perspectives of determining the free parameters of the theory through cosmological observations.

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Frank Saueressig, Giulia Gubitosi, Chris Ripken. 2019-01-07. Scales and hierachies in asymptotically safe quantum gravity: a review. https://arxiv.org/abs/1901.01731

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