English

One-loop quantum gravitational backreaction on the local Hubble rate

General Relativity and Quantum Cosmology 2019-04-15 v2 High Energy Physics - Theory

Abstract

We determine corrections to the Hubble rate due to graviton loops in a cosmological background spacetime of constant deceleration parameter. The corrections are gauge-invariant, based on a recent proposal for all-order gauge-invariant observables in perturbative quantum gravity. We find explicit expressions for the cases of matter- and radiation-dominated eras and slow-roll inflation with vanishing second slow-roll parameter. Interestingly, in the latter case the corrections can be described by a quantum-corrected first slow-roll parameter, which brings the spacetime closer to de Sitter space.

Keywords

Cite

@article{arxiv.1806.11124,
  title  = {One-loop quantum gravitational backreaction on the local Hubble rate},
  author = {Markus B. Fröb},
  journal= {arXiv preprint arXiv:1806.11124},
  year   = {2019}
}

Comments

35 pages, includes comparison with other approaches, matches published version

R2 v1 2026-06-23T02:45:16.263Z