Perturbative Quantum Gravity Comes of Age

Abstract

I argue that cosmological data from the epoch of primordial inflation is catalyzing the maturation of quantum gravity from speculation into a hard science. I explain why quantum gravitational effects from primordial inflation are observable. I then review what has been done, both theoretically and observationally, and what the future holds. I also discuss what this tells us about quantum gravity.

arXiv comment64 pages, 6 figures, review article written for "One Hundred Years of General Relativity"

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Cited by in corpus (63)

• Holographic inflation
• Inflationary universe from higher-derivative quantum gravity
• Review of the No-Boundary Wave Function
• Effective long wavelength scalar dynamics in de Sitter
• Constraining some Horndeski gravity theories
• Characters of different secular effects in various patches of de Sitter space
• Quantum-gravitational effects on gauge-invariant scalar and tensor perturbations during inflation: The de Sitter case
• Infrared dynamics of massive scalars from the complementary series in de Sitter space
• Vacuum Fluctuations of a Scalar Field during Inflation: Quantum versus Stochastic Analysis
• Quantum Gravity: A Brief History of Ideas and Some Prospects
• Mode-sum construction of the covariant graviton two-point function in the Poincaré patch of de Sitter space
• The maximum sizes of large scale structures in alternative theories of gravity
• Graviton Loop Corrections to Vacuum Polarization in de Sitter in a General Covariant Gauge
• Beyond-one-loop quantum gravity action yielding both inflation and late-time acceleration
• Inflationary spectra with inverse-volume corrections in loop quantum cosmology and their observational constraints from Planck 2015 data
• Equivalence of Adiabatic and DeWitt-Schwinger renormalization schemes
• Inflationary universe from higher derivative quantum gravity coupled with scalar electrodynamics
• Vacuum and Gravitons of Relic Gravitational Waves, and Regularization of Spectrum and Energy-Momentum Tensor
• One-loop quantum electrodynamic correction to the gravitational potentials on de Sitter spacetime
• Lagrangian constraints and renormalization of 4D gravity
• Renormalization of the inflationary perturbations revisited
• One loop graviton corrections to dynamical photons in de Sitter
• Foliation, jet bundle and quantization of Einstein gravity
• Quantum gravity corrections to the conformally coupled scalar self-mass-squared on de Sitter II: kinetic-conformal cross terms
• One-loop renormalization of a gravity-scalar system
• Large scale structures and the cubic galileon model
• Adiabatic regularization with a Yukawa interaction
• Cosmic structure sizes in generic dark energy models
• Quantum Effects of Mass on Scalar Field Correlations and Fluctuations during Inflation
• Inflation with non-canonical scalar fields revisited
• A quantum heating as an alternative of reheating
• Debye mass in de Sitter space
• Precision Predictions for the Primordial Power Spectra of Scalar Potential Models of Inflation
• Primordial fluctuations from complex AdS saddle points
• Remembrance of Things Past
• Constraining phantom braneworld model from cosmic structure sizes
• Dirac fermion, cosmological event horizons and quantum entanglement
• Covariant and infrared-free graviton two-point function in de Sitter spacetime II
• "Massless" spin-2 field in de Sitter space
• Rotating Killing horizons in generic $F(R)$ gravity theories
• Vacuum states for gravitons field in de Sitter space
• Massless minimal quantum scalar field with an asymmetric self interaction in de Sitter spacetime
• Final Thoughts on the Power Spectra of Scalar Potential Models
• Foliation-based approach to quantum gravity and applications to astrophysics
• Gupta-Bleuler quantization for linearized gravity in de Sitter spacetime
• Covariant quantum corrections to a scalar field model inspired by nonminimal natural inflation
• Graviton backreaction on the local cosmological expansion in slow-roll inflation
• A small non-vanishing cosmological constant from the Krein-Gupta-Bleuler vacuum
• Abelian Higgs model in power-law inflation: the propagators in the unitary gauge
• From Non-trivial Geometries to Power Spectra and Vice Versa
• Testing an Ansatz for the Leading Secular Loop Corrections from Quantum Gravity during Inflation
• The Effect of Features on the Functional Form of the Scalar Power Spectrum
• Improving the Single Scalar Consistency Relation
• Ultraviolet-regularized power spectrum without infrared distortions in cosmological spacetimes
• Covariant Effective Action for Scalar-Tensor Theories of Gravity
• Inflationary magnetogenesis and non-local actions: The conformal anomaly
• Implementation of cosmological bounce inflation with Nojiri-Odintsov generalized holographic dark fluid
• Physical scale adiabatic regularization in cosmological spacetimes
• Stochastic wave equation with thermal noise in an expanding universe
• Hartle-Hawking state in the real-time formalism
• Gravitational fermion creation during an anisotropic phase of cosmological expansion
• Universal horizons and Hawking radiation in nonprojectable 2d Hořava gravity coupled with a non-relativistic scalar field
• Sub-Leading Logarithms for Scalar Potential Models on de Sitter