Slow-roll inflation with a Gauss-Bonnet correction
read the original abstract
We consider slow-roll inflation for a single scalar field with an arbitrary potential and an arbitrary nonminimal coupling to the Gauss-Bonnet term. By introducing a combined hierarchy of Hubble and Gauss-Bonnet flow functions, we analytically derive the power spectra of scalar and tensor perturbations. The standard consistency relation between the tensor-to-scalar ratio and the spectral index of tensor perturbations is broken. We apply this formalism to a specific model with a monomial potential and an inverse monomial Gauss-Bonnet coupling and constrain it by the 7-year Wilkinson Microwave Anisotropy Probe data. The Gauss-Bonnet term with a positive (or negative) coupling may lead to a reduction (or enhancement) of the tensor-to-scalar ratio and hence may revive the quartic potential ruled out by recent cosmological data.
This paper has not been read by Pith yet.
Forward citations
Cited by 4 Pith papers
-
Beyond $f(\phi)\mathcal{G}$: Gauss--Bonnet inflation with $\mu(\phi,X)$
A phase-space gating function μ(φ,X) localizes Gauss-Bonnet contributions to a finite e-fold window in inflation while preserving ghost and gradient stability for scalar and tensor modes.
-
Positive Running of the Spectral Index for Scalar Theory and Modified Gravity
Positive running of the spectral index is achievable in Einstein-Gauss-Bonnet gravity with viable inflation, unlike standard scalar field and F(R) models which face challenges.
-
Towards Stochastic Inflation in Higher-Curvature Gravity
Stochastic inflation with Gauss-Bonnet coupling to the inflaton yields first-passage-time estimates of the scalar power spectrum and PBH mass fraction in slow-roll and ultra-slow-roll limits.
-
Gravitational waves production during preheating within GB gravity with monomial coupling
In Gauss-Bonnet inflation with monomial potential and coupling, gravitational waves from preheating produce a present-day energy density spectrum consistent with Planck constraints when the coupling strength, equation...
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.