Asymptotically safe cosmology - a status report
  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.
