${\mathcal{R}}^2$ Quantum Corrected Scalar Field Inflation

Abstract

String theory enjoys an elevated role among quantum gravity theories, since it seems to be the most consistent UV completion of general relativity and the Standard Model. However, it is hard to verify the existence of this underlying theory on terrestrial accelerators. One way to probe string theory is to study its imprints on the low-energy effective inflationary Lagrangian, which are quantified in terms of high energy correction terms. It is highly likely, thus, to find higher order curvature terms combined with string moduli, that is scalar fields, since both these types of interactions and matter fields appear in string theory. In this work we aim to stress the probability that the inflationary dynamics are controlled by the synergy of scalar fields and higher order curvature terms. Specifically, we shall consider a well motivated quantum corrected canonical scalar field theory, with the quantum corrections being of the ${\mathcal{R}}^2$ type. The reason for choosing minimally coupled scalar theory is basically because if scalar fields are evaluated in their vacuum configuration, they will either be minimally coupled or conformally coupled. Here we choose the former case, and the whole study shall be performed in the string frame (Jordan frame), in contrast to similar studies in the literature where the Einstein frame two scalar theory is considered. We derive the field equations of the quantum-corrected theory at leading order and we present the form the slow-roll indices obtain for the quantum corrected theory. We exemplify our theoretical framework by using the quadratic inflation model, and as we show, the ${\mathcal{R}}^2$ quantum corrected quadratic inflation model produces a viable inflationary phenomenology, in contrast with the simple quadratic inflation model.

arXiv commentNPB Accepted

References in corpus (24)

• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• Extended Theories of Gravity
• Modified Gravity Theories on a Nutshell: Inflation, Bounce and Late-time Evolution
• Planck 2018 results. X. Constraints on inflation
• The Standard Model Higgs boson as the inflaton
• Particle Physics Models of Inflation and the Cosmological Density Perturbation
• Sensitivity Studies for Third-Generation Gravitational Wave Observatories
• Palatini Approach to Modified Gravity: f(R) Theories and Beyond
• Beyond LISA: Exploring Future Gravitational Wave Missions
• Inflationary Cosmology
• Fundamental Physics with the Square Kilometre Array
• The Quest for B Modes from Inflationary Gravitational Waves
• Black holes, cosmological solutions, future singularities, and their thermodynamical properties in modified gravity theories
• Classical evolution and quantum generation in generalized gravity theories including string corrections and tachyon: Unified analyses
• LISA for Cosmologists: Calculating the Signal-to-Noise Ratio for Stochastic and Deterministic Sources
• Higgs Scalaron Mixed Inflation
• Sensitivity to a Frequency-Dependent Circular Polarization in an Isotropic Stochastic Gravitational Wave Background
• Unification of Constant-roll Inflation and Dark Energy with Logarithmic $R^2$-corrected and Exponential $F(R)$ Gravity
• Scalaron the healer: removing the strong-coupling in the Higgs- and Higgs-dilaton inflations
• Higgs Starobinsky Inflation
• On the covariant formalism of the effective field theory of gravity and leading order corrections
• Confrontation of a Double Inflationary Cosmological Model with Observations
• Canonical Scalar Field Inflation with String and $R^2$-Corrections
• Power-Law $f(R)$ Gravity Corrected Canonical Scalar Field Inflation

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• Importance of being nonminimally coupled: Scalar Hawking radiation from regular black holes
• Kinetic Axion Dark Matter in String Corrected $f(R)$ Gravity
• Towards a unified interpretation of the early Universe in $R^2$-corrected dark energy model of $F(R)$ gravity
• Self-tuning inflation
• Gravity Rainbow Effects on Higher Curvature Modification of R2 inflation
• Inflation in simple one-loop effective potentials of perturbative quantum gravity