New type of hill-top inflation

Abstract

We suggest a new type of hill-top inflation originating from the initial conditions in the form of the microcanonical density matrix for the cosmological model with a large number of quantum fields conformally coupled to gravity. Initial conditions for inflation are set up by cosmological instantons describing underbarrier oscillations in the vicinity of the inflaton potential maximum. These periodic oscillations of the inflaton field and cosmological scale factor are obtained within the approximation of two coupled oscillators subject to the slow roll regime in the Euclidean time. This regime is characterized by rapid oscillations of the scale factor on the background of a slowly varying inflaton, which guarantees smallness of slow roll parameters $\epsilon$ and $\eta$ of the following inflation stage. A hill-like shape of the inflaton potential is shown to be generated by logarithmic loop corrections to the tree-level asymptotically shift-invariant potential in the non-minimal Higgs inflation model and $R^2$-gravity. The solution to the problem of hierarchy between the Planckian scale and the inflation scale is discussed within the concept of conformal higher spin fields, which also suggests the mechanism bringing the model below the gravitational cutoff and, thus, protecting it from large graviton loop corrections.

discussion of the gravitational cutoff is included, references added

References in corpus (15)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• The Standard Model Higgs boson as the inflaton
• Higgs inflation: consistency and generalisations
• Inflation scenario via the Standard Model Higgs boson and LHC
• Black Hole Bound on the Number of Species and Quantum Gravity at LHC
• Correlation Functions in Stochastic Inflation
• Higher spins in AdS_5 at one loop: vacuum energy, boundary conformal anomalies and AdS/CFT
• Cosmological Landscape From Nothing: Some Like It Hot
• Thermodynamics via Creation from Nothing: Limiting the Cosmological Constant Landscape
• Why there is something rather than nothing (out of everything)?
• Anomaly Driven Cosmology: Big Boost Scenario and AdS/CFT Correspondence
• Origin of inflation in CFT driven cosmology: $R^2$-gravity and non-minimally coupled inflaton models
• Are $R^2$- and Higgs-inflations really unlikely?
• Replication Regulates Volume Weighting in Quantum Cosmology
• Spacetime Average Density (SAD) Cosmological Measures

Cited by in corpus (8)

• Palatini inflation in models with an $R^2$ term
• CFT driven cosmology and conformal higher spin fields
• Notes on conformal anomaly, nonlocal effective action and the metamorphosis of the running scale
• Weyl Anomaly and Initial Singularity Crossing
• Topological Inflation
• Instanton Tunneling for De Sitter Space with Real Projective Spatial Sections
• Kinetic dominance and the wavefunction of the universe
• Preferred basis, decoherence and a quantum state of the Universe