BONANNO, Alfio MaurizioAlfio MaurizioBONANNOSaueressig, FrankFrankSaueressig2020-11-172020-11-1720171631-0705http://hdl.handle.net/20.500.12386/28387Asymptotic 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 the building of a cosmological model. 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 improvement of the renormalization group permit a direct comparison to cosmological observations as, e.g., Planck data.STAMPAenArticle10.1016/j.crhy.2017.02.0022-s2.0-85019870331000404687900007https://www.sciencedirect.com/science/article/pii/S16310705173002702017CRPhy..18..254BFIS/05 - ASTRONOMIA E ASTROFISICAERC sectors::Physical Sciences and Engineering::PE9 Universe sciences: astro-physics/chemistry/biology; solar systems; stellar, galactic and extragalactic astronomy, planetary systems, cosmology, space science, instrumentation