REVIEW 4 cited by
Quantum gravity and scale symmetry in cosmology
Not yet reviewed by Pith; the record is open.
This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.
SPECIMEN: schema-true, not a live event
T0 review · schema-true
One-sentence machine reading of the paper's core claim.
pith:XXXXXXXX · record.json · timestamp
read the original abstract
We discuss predictions for cosmology which result from the scaling solution of functional flow equations for a quantum field theory of gravity. A scaling solution is necessary to render quantum gravity renormalizable. Our scaling solution is directly connected to the quantum effective action for the metric coupled to a scalar field. It includes all effects of quantum fluctuations and is invariant under general coordinate transformations. Solving the cosmological field equations derived by variation of the quantum effective action provides for a detailed quantitative description of the evolution of the universe. The \qq{beginning state} of the universe is found close to an ultraviolet fixed point of the flow equation. It can be described by an inflationary epoch, with approximate scale invariance of the observed primordial fluctuation spectrum explained by approximate quantum scale symmetry. Overall cosmology realizes a dynamical crossover from the ultraviolet fixed point to an infrared fixed point which is approached in the infinite future. Present cosmology is close to the infrared fixed point. It features dynamical dark energy mediated by a light scalar field. The tiny mass of this cosmon arises from its role as a pseudo Goldstone boson of spontaneously broken quantum scale symmetry. The extremely small value of the present dark energy density in Planck units results dynamically as a consequence of the huge age of the universe. The cosmological constant problem finds a dynamical solution. We present a detailed quantitative computation of the scaling solution for the scalar effective potential and the field-dependent coefficient of the curvature scalar. This allows for further quantitative predictions.
Forward citations
Cited by 4 Pith papers
-
The fermion sector of the SMEFT from asymptotically safe gravity
In a toy model of one quark generation, asymptotically safe gravity predicts four-fermion SMEFT coefficients are either Planck-scale suppressed or zero, with exceptions only at very large gravitational coupling.
-
Impact of quantum gravity on the UV sensitivity of extremal black holes
Asymptotically safe quantum gravity predicts a positive Goroff-Sagnotti Wilson coefficient at the Planck scale, which would keep extremal Kerr black hole tidal forces finite, but the paper's bound on the quantum gravi...
-
Self-consistent graviton spectral function in Lorentzian quantum gravity
A self-consistent spectral renormalisation group computation yields a positive, normalizable graviton spectral function with a massless pole and a multi-graviton continuum decaying as 1/(λ² log³ λ²).
-
Fermi scale from quantum gravity scaling solution
The Fermi/Planck ratio is claimed to be predictable from the analyticity of the quantum-gravity scaling solution for the cosmon-Higgs coupling, with numerics showing the coupling flows to a tiny, near-critical value.
Discussion (0). Continue with ORCID to comment.