Contrary to general belief, quantum gravity can have important consequences for present day experiments and cosmological observations. It can predict some couplings of the standard model of particle physics. Quantum fluctuations of the metric determine the quartic self-interaction of the Higgs-scalar at an energy scale close to the Planck mass. Extrapolating the running couplings to the electroweak scale, the mass of the Higgs boson has been predicted in the range found later by experiment. The scaling solution of quantum gravity for scalar potentials in cosmology is found to have a form that predicts both a very early inflationary epoch and late dynamical dark energy. The beginning of the Universe is a scale invariant state that may be called „great emptiness“. Functional renormalisation permits the computation of fluctuation effects of the metric. Quantum gravity can be formulated as a non-perturbatively renormalisable quantum field theory, in close analogy to the other fundamental interactions. The quantum scale symmetry associated to the ultraviolet fixed point has far reaching implications for particle physics and cosmology.