Constant-roll inflation in scalar-tensor gravity

Abstract

We generalize the notion of constant-roll inflation earlier introduced in General Relativity (GR) and $f(R)$ gravity to inflationary models in more general scalar-tensor gravity. A number of novel exact analytic solutions for a FLRW spatially flat cosmological background is found for this case. All forms of the scalar field potential and its coupling to gravity producing the exact de Sitter solution, while the scalar field is varying, are presented. In the particular cases of induced gravity and GR with a non-minimally coupled scalar field, all constant-roll inflationary solutions are found. In the former case they represent power-law inflation, while in the latter case the solution is novel and more complicated. Comparison of scalar perturbations generated during such inflation in induced gravity with observational data shows that the constant-roll parameter should be small, similar to constant-roll inflation in GR and $f(R)$ gravity. Then the solution reduces to the standard slow-roll one with small corrections.

15 pages, 3 figures; matches published version

References in corpus (2)

• Consistency relation for $R^p$ inflation
• Rapid roll Inflation with Conformal Coupling

Cited by in corpus (33)

• Geodesic deviation, Raychaudhuri equation, Newtonian limit, and tidal forces in Weyl-type $f(Q,T)$ gravity
• Constant roll and primordial black holes
• Squeezed bispectrum and one-loop corrections in transient constant-roll inflation
• Beyond Einstein's General Relativity: Hybrid metric-Palatini gravity and curvature-matter couplings
• Anisotropy screening in Horndeski cosmologies
• Brane Constant-roll Inflation
• Constant roll inflation in multifield models
• New class of hybrid metric-Palatini scalar-tensor theories of gravity
• Primordial black holes and induced gravitational waves from logarithmic non-Gaussianity
• Constant-roll inflation in the generalized SU(2) Proca theory
• Nonminimal coupling inflation with constant slow roll
• Natural Inflation with non minimal coupling to gravity in $R^2$ gravity under the Palatini formalism
• Constant-Roll Inflation in modified $f(R,\varphi )$ gravity model using Palatini Formalism
• Generalized scalar-tensor theory of gravity reconstruction from physical potentials of a scalar field
• Anisotropic constant-roll inflation for the Dirac-Born-Infeld model
• Constant roll and non-Gaussian tail in light of logarithmic duality
• Large-scale gauge spectra and pseudoscalar couplings
• Gauss-Bonnet inflation with a constant rate of roll
• On the constant roll complex scalar field inflationary models
• Reconstruction methods and the amplification of the inflationary spectrum
• Constant-roll, cosmic acceleration, and massive neutrinos
• The refractive index of the relic gravitons and the nHz band
• Analytical Insights into Constant-Roll Condition: Extending the Paradigm to Non-Canonical Models
• Holographic inflation and holographic dark energy from entropy of the anti-de Sitter black hole
• Relic gravitons and pulsar timing arrays: a theoretical viewpoint
• The Trans-Planckian Censorship Conjecture in different frameworks of viable inflation
• Scalar-tensor cosmologies in a minisuperspace formulation: a case study
• Flat spectra of cosmic gravitons in the nHz and audio bands
• Dynamical Shortcomings in the Generalized SU(2) Proca Theory: Challenges for Cosmic Acceleration
• Constant-roll inflation and primordial black holes within Barrow entropic framework
• Can Gibbons-Hawking Radiation and Inflation Arise Due to Spacetime Quanta?
• Relic gravitons at intermediate frequencies and the expansion history of the Universe
• Anisotropic constant-roll k-inflation model