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arXiv · 2309.10785

Quantum Gravity from dynamical metric fluctuations

Jan M. Pawlowski·Manuel Reichert
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Abstract

In this contribution, we discuss the asymptotic safety scenario for quantum gravity by evaluating the correlation functions of dynamical metric fluctuations. This is done with a functional renormalisation group approach that disentangles dynamical metric fluctuations from the background metric. We detail the derivation of the respective flow equations on space-time manifolds with Euclidean and Lorentzian signatures and discuss the diffeomorphism symmetry constraints on the flow as well as the convergence of systematic vertex expansion schemes. We then proceed with a comprehensive review of results of momentum-dependent correlation functions at vanishing cutoff scale, the phase structure of the asymptotically safe Standard Model, and spectral properties of asymptotically safe gravity from direct computations in space-times with Lorentzian signatures such as the graviton spectral function.

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Jan M. Pawlowski, Manuel Reichert. 2023-09-19. Quantum Gravity from dynamical metric fluctuations. https://arxiv.org/abs/2309.10785

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