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arXiv · 2401.11559

Scale-dependent cosmology from effective quantum gravity in the invariant framework

Nicolas R. Bertini·Davi C. Rodrigues·Ilya L. Shapiro
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Abstract

We explore the possibility of a consistent cosmology based on the gauge-fixing independent running of the gravitational and cosmological constants ($G$ and $\Lambda$) in the framework of effective quantum gravity. In particular, their running in this framework was found to satisfy $G \propto \Lambda^4$. In the cosmological setting, the covariance of the theory provides energy conservation relations, which are impossible to satisfy with the unique scale parameter. However, by introducing the second sub-dominant scale corresponding to the higher-loop corrections and higher-derivative terms, one can close the system of equations for the running of parameters and arrive at the consistent cosmological solutions. This approach yields a change in the cosmological expansion history that affects the ratio of the Hubble parameter today to the Hubble parameter at high redshift.

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Nicolas R. Bertini, Davi C. Rodrigues, Ilya L. Shapiro. 2024-01-21. Scale-dependent cosmology from effective quantum gravity in the invariant framework. https://doi.org/10.1016/j.dark.2024.101502

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