Primordial black holes and induced gravitational waves from inflation in the Horndeski theory of gravity

Abstract

We investigate the production of primordial black holes (PBHs) and scalar-induced gravitational waves (GWs) for cosmological models in the Horndeski theory of gravity. The cosmological models of our interest incorporate the derivative self-interaction of the scalar field and the kinetic coupling between the scalar field and gravity. We show that the scalar power spectrum of the primordial fluctuations can be enhanced on small scales due to these additional interactions. Thus, the formation of PBHs and the production of induced GWs are feasible for our model. Parameterizing the scalar power spectrum with a local Gaussian peak, we first estimate the abundance of PBHs and the energy spectrum of GWs produced in the radiation-dominated era. Then, to explain the small-scale enhancement in the power spectrum, we reconstruct the inflaton potential and self-coupling functions from the power spectrum and their spectral tilt. Our results show that the small-scale enhancement in the power spectrum can be explained by the local feature, either a peak or dip, in the self-coupling function rather than the local feature in the inflaton potential.

25 pages, 3 figures

References in corpus (9)

• Primordial Black Holes as Dark Matter
• Gravitational Wave Spectrum Induced by Primordial Scalar Perturbations
• Gravitational-wave sensitivity curves
• The cosmological gravitational wave background from primordial density perturbations
• Solar-Mass Primordial Black Holes Explain NANOGrav Hint of Gravitational Waves
• Unified treatment of cosmological perturbations from super-horizon to small scales
• Scalar induced gravitational waves in inflation with gravitationally enhanced friction
• Primordial black holes and secondary gravitational waves from inflationary model with a non-canonical kinetic term
• Black Hole Remnants in the Early Universe

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• Primordial Black Hole Formation in Starobinsky's Linear Potential Model
• Primordial black holes and scalar-induced gravitational waves from the generalized Brans-Dicke theory
• Model-independent reconstruction of the primordial curvature power spectrum from PTA data
• The Inflaton that Could : Primordial Black Holes and Second Order Gravitational Waves from Tachyonic Instability induced in Higgs-$R^2$ Inflation
• The reheating constraints to natural inflation in Horndeski gravity