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arXiv · 2111.13232

Lorentzian quantum gravity and the graviton spectral function

Jannik Fehre·Daniel F. Litim·Jan M. Pawlowski·Manuel Reichert
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Abstract

We present the first direct and non-perturbative computation of the graviton spectral function in quantum gravity. This is achieved with the help of a novel Lorentzian renormalisation group approach, combined with a spectral representation of correlation functions. We find a positive graviton spectral function, showing a massless one-graviton peak and a multi-graviton continuum with an asymptotically safe scaling for large spectral values. We also study the impact of a cosmological constant. Further steps to investigate scattering processes and unitarity in asymptotically safe quantum gravity are indicated.

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Jannik Fehre, Daniel F. Litim, Jan M. Pawlowski, Manuel Reichert. 2021-11-25. Lorentzian quantum gravity and the graviton spectral function. https://arxiv.org/abs/2111.13232

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