Amplification of the Primordial Gravitational Waves Energy Spectrum by a Kinetic Scalar in $F(R)$ Gravity

Abstract

In this work we consider a combined theoretical framework comprised by $F(R)$ gravity and a kinetic scalar field. The kinetic energy of the scalar field dominates over its potential for all cosmic times, and the kinetic scalar potential is chosen to be small and non-trivial. In this case, we show that the primordial gravitational wave energy spectrum of vacuum $F(R)$ gravity is significantly enhanced and can be detectable in future interferometers. The kinetic scalar thus affects significantly the inflationary era, since it extends its duration, but also has an overall amplifying effect on the energy spectrum of pure $F(R)$ gravity primordial gravitational waves. The form of the signal is characteristic for all these theories, since it is basically flat and should be detectable from all future gravitational wave experiments for a wide range of frequencies, unless some unknown damping factor occurs due to some unknown physical process.

Astroparticle Physics in press

References in corpus (31)

• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• Palatini Approach to Modified Gravity: f(R) Theories and Beyond
• Inflationary Cosmology
• Maximal freedom at minimum cost: linear large-scale structure in general modifications of gravity
• Constraining f(R) Gravity as a Scalar Tensor Theory
• Limit to General Relativity in f(R) theories of gravity
• Improved Calculation of the Primordial Gravitational Wave Spectrum in the Standard Model
• Implications of the NANOGrav results for inflation
• Probing reheating temperature of the universe with gravitational wave background
• The evolution of density perturbations in f(R) gravity
• Junction Conditions in f(R) Theories of Gravity
• Primordial gravitational waves from NANOGrav: a broken power-law approach
• Inflation and the Scale Dependent Spectral Index: Prospects and Strategies
• Precision calculations of the gravitational wave background spectrum from inflation
• Sensitivity to a Frequency-Dependent Circular Polarization in an Isotropic Stochastic Gravitational Wave Background
• Aspects of cosmological expansion in F(R) gravity models
• Blue-tilted Tensor Spectrum and Thermal History of the Universe
• Prospects for direct detection of primordial gravitational waves
• Relic Gravitational Waves in the Accelerating Universe
• Cosmic history of viable exponential gravity: Equation of state oscillations and growth index from inflation to dark energy era
• Imprints of Relic Gravitational Waves in Cosmic Microwave Background Radiation
• Blue-tilted inflationary tensor spectrum and reheating in the light of NANOGrav results
• Spectrum of Primordial Gravitational Waves in Modified Gravities: A Short Overview
• $f(R)$ gravity constrained by PPN parameters and stochastic background of gravitational waves
• Constraints on Scalar and Tensor spectra from $N_{eff}$
• Inflationary Attractors in $F(R)$ Gravity
• Primordial Gravitational Waves Predictions for GW170817-compatible Einstein-Gauss-Bonnet Theory
• Pre-Inflationary Bounce Effects on Primordial Gravitational Waves of $f(R)$ Gravity
• Kinetic Axion $F(R)$ Gravity Inflation
• Cosmology with the Einstein Telescope: No Slip Gravity Model and Redshift Specifications
• Higher-Curvature Corrections and Tensor Modes

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• Horizon-scale tests of gravity theories and fundamental physics from the Event Horizon Telescope image of Sagittarius A${}^{\ast }$
• Inflationary interpretation of the stochastic gravitational wave background signal detected by pulsar timing array experiments
• The challenge of ruling out inflation via the primordial graviton background
• Broken blue-tilted inflationary gravitational waves: a joint analysis of NANOGrav 15-year and BICEP/Keck 2018 data
• Inflation, the Hubble Tension and Early Dark Energy: an alternative overview
• Towards a reliable calculation of relic radiation from primordial gravitational waves
• Inflationary Potential as seen from Different Angles: Model Compatibility from Multiple CMB Missions
• Tracking the Multifield Dynamics with Cosmological Data: A Monte Carlo approach
• Observable Gravitational Waves from Hyperkination in Palatini Gravity and Beyond
• The Effect of Non-minimally Coupled Scalar Field on Gravitational Waves from First-order Vacuum Phase Transitions
• Primordial gravitational waves from spontaneous Lorentz symmetry breaking
• Gravitational Waves from a Gauge Field Non-minimally Coupled to Gravity