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arXiv · 1702.04137

Asymptotically safe cosmology - a status report

Alfio Bonanno·Frank Saueressig
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Abstract

Asymptotic Safety, based on a non-Gaussian fixed point of the gravitational renormalization group flow, provides an elegant mechanism for completing the gravitational force at sub-Planckian scales. At high energies the fixed point controls the scaling of couplings such that unphysical divergences are absent while the emergence of classical low-energy physics is linked to a crossover between two renormalization group fixed points. These features make Asymptotic Safety an attractive framework for cosmological model building. The resulting scenarios may naturally give rise to a quantum gravity driven inflationary phase in the very early universe and an almost scale-free fluctuation spectrum. Moreover, effective descriptions arising from an renormalization group improvement permit a direct comparison to cosmological observations as, e.g. Planck data.

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Alfio Bonanno, Frank Saueressig. 2017-02-14. Asymptotically safe cosmology - a status report. https://doi.org/10.1016/j.crhy.2017.02.002

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