Self-consistent graviton spectral function in Lorentzian quantum gravity
Abstract
We present the first fully self-consistent computation of the graviton spectral function in quantum gravity, using the spectral renormalisation group for gravity put forward in arXiv:2111.13232v2 [hep-th] within a physical mass-shell renormalisation scheme. Here, self-consistency refers to the fact that the full non-perturbative spectral function is used in the diagrams, including the scattering continuum. We find a positive graviton spectral function with a massless one-graviton peak and a multi-graviton continuum with a close-to-quadratic spectral decay in the ultraviolet. Within the physical on-shell renormalisation scheme, the graviton satisfies the sum rule of an asymptotic state and features a unit total spectral weight. We briefly discuss the implications of the physical formulation for the computation of scattering processes and investigations of unitarity in asymptotically safe quantum gravity.
Cite
@article{arxiv.2507.22169,
title = {Self-consistent graviton spectral function in Lorentzian quantum gravity},
author = {Jan M. Pawlowski and Manuel Reichert and Jonas Wessely},
journal= {arXiv preprint arXiv:2507.22169},
year = {2025}
}
Comments
11 pages, 5 figures