Tobias Denz (Heidelberg University)

  • Date: 30 APRIL 2021  from 14:30 to 15:30

Graviton spectral functions

We reconstruct the Lorentzian graviton propagator in asymptotically safe quantum gravity from Euclidean data. The reconstruction is applied to both the dynamical fluctuation graviton and the background graviton propagator, where the background spectral function necessarily has negative parts. In turn, the spectral function of the dynamical graviton is positive. We argue that the latter enters cross sections and other observables in asymptotically safe quantum gravity. Hence, its positivity may hint at the unitarity of asymptotically safe quantum gravity