On the Predictiveness of Single-Field Inflationary Models

Abstract

We re-examine the predictiveness of single-field inflationary models and discuss how an unknown UV completion can complicate determining inflationary model parameters from observations, even from precision measurements. Besides the usual naturalness issues associated with having a shallow inflationary potential, we describe another issue for inflation, namely, unknown UV physics modifies the running of Standard Model (SM) parameters and thereby introduces uncertainty into the potential inflationary predictions. We illustrate this point using the minimal Higgs Inflationary scenario, which is arguably the most predictive single-field model on the market, because its predictions for $A_s$, $r$ and $n_s$ are made using only one new free parameter beyond those measured in particle physics experiments, and run up to the inflationary regime. We find that this issue can already have observable effects. At the same time, this UV-parameter dependence in the Renormalization Group allows Higgs Inflation to occur (in principle) for a slightly larger range of Higgs masses. We comment on the origin of the various UV scales that arise at large field values for the SM Higgs, clarifying cut off scale arguments by further developing the formalism of a non-linear realization of $\mathrm{S}{\mathrm{U}}_{\mathrm{L}}(2)\times \mathrm{U}(1)$ in curved space. We discuss the interesting fact that, outside of Higgs Inflation, the effect of a non-minimal coupling to gravity, even in the SM, results in a non-linear EFT for the Higgs sector. Finally, we briefly comment on post BICEP2 attempts to modify the Higgs Inflation scenario.

31 pp, 4 figures v4: Minor correction to section 3.1. Main arguments and conclusions unchanged

References in corpus (8)

• The Standard Model Higgs boson as the inflaton
• Renormalization Group Evolution of the Standard Model Dimension Six Operators III: Gauge Coupling Dependence and Phenomenology
• Higgs inflation: consistency and generalisations
• Power-counting and the Validity of the Classical Approximation During Inflation
• On Inflation with Non-minimal Coupling
• The Best Inflationary Models After Planck
• Unitarizing Higgs Inflation
• On the Power Counting in Effective Field Theories

Cited by in corpus (45)

• The Standard Model as an Effective Field Theory
• Living beyond the edge: Higgs inflation and vacuum metastability
• Higgs inflation
• Higgs inflation from Standard Model criticality
• Higgs inflation with loop corrections in the Palatini formulation
• Theory and Phenomenology of Planckian Interacting Massive Particles as Dark Matter
• On the robustness of the primordial power spectrum in renormalized Higgs inflation
• Quantum corrections to quartic inflation with a non-minimal coupling: metric vs. Palatini
• de Sitter Vacua in Type IIB String Theory: Classical Solutions and Quantum Corrections
• Predictions on mass of Higgs portal scalar dark matter from Higgs inflation and flat potential
• Quantum Effects in Palatini Higgs Inflation
• UV (in)sensitivity of Higgs inflation
• Overshooting, Critical Higgs Inflation and Second Order Gravitational Wave Signatures
• Unifying inflation and dark matter with the Peccei-Quinn field: observable axions and observable tensors
• Higgs-Dilaton cosmology: Universality vs. criticality
• Quantum corrections in Higgs inflation: the Standard Model case
• From inflation to cosmological electroweak phase transition with a complex scalar singlet
• Extending Higgs Inflation with TeV Scale New Physics
• Higgs Inflation as Nonlinear Sigma Model and Scalaron as its $\sigma$-meson
• A Strong Electroweak Phase Transition from the Inflaton Field
• Unitarity and predictiveness in new Higgs inflation
• The Problem with False Vacuum Higgs Inflation
• Observational signatures of Higgs inflation
• Critical Higgs inflation in a Viable Motivated Model
• BICEP/Keck data and Quadratic Gravity
• Asymptotically Safe Higgs Inflation
• Examining the neutrino option
• Higher derivatives and power spectrum in effective single field inflation
• Power-counting during single-field slow-roll inflation
• Preheating from target space curvature and unitarity violation: Analysis in field space
• Power Spectrum of Inflationary Attractors
• Inflationary attractors and radiative corrections in light of ACT data
• Testing scale-invariant inflation against cosmological data
• Matching and running sensitivity in non-renormalizable inflationary models
• Higgs inflation and cosmological electroweak phase transition with N scalars in the post-Higgs era
• Chiral gravitational waves and primordial black holes in UV-protected Natural Inflation
• Low Scale Inflation at High Energy Colliders and Meson Factories
• Quantum Gravitational Contributions to the Standard Model Effective Potential and Vacuum Stability
• Inflation and pseudo-Goldstone Higgs boson
• Axion-Sterile-Neutrino Dark Matter
• On the strong coupling scale in Higgs G-inflation
• Hearing Higgs with Gravitational Wave Detectors
• Can Higgs Inflation be Saved with High-scale Supersymmetry ?
• Ultraviolet Sensitivity of Peccei-Quinn Inflation
• Dark Matter Freeze-in from a $Z^{\prime }$ Reheaton