Hypernatural inflation

Abstract

We constructed a model of natural inflation in the context of $\alpha$-attractor supergravity, in which both the dilaton field and the axion field are light during inflation, and the inflaton may be a combination of the two. The T-model version of this theory is defined on the Poincare disk with radius |Z| = 1. It describes a Mexican hat potential with the flat axion direction corresponding to a circle of radius |Z| < 1. The axion decay constant $f_a$ in this theory can be exponentially large because of the hyperbolic geometry of the Poincare disk. Depending on initial conditions, this model may describe $\alpha$-attractor inflation driven by the radial component of the inflaton field, natural inflation driven by the axion field, or a sequence of these two regimes. We also construct the E-model version of this theory, which has similar properties. In addition, we describe generalized $\alpha$-attractor models where the potential can be singular at the boundary of the moduli space, and show that they can provide a simple solution for the problem of initial conditions for the models with plateau potentials.

25 pages, 8 figures; v2: published version with references added and discussion extended

References in corpus (20)

• Monodromy in the CMB: Gravity Waves and String Inflation
• The Unity of Cosmological Attractors
• Cosmology with Nilpotent Superfields
• Flaxion: a minimal extension to solve puzzles in the standard model
• Curvature and isocurvature perturbations in two-field inflation
• Mass hierarchies and non-decoupling in multi-scalar field dynamics
• Cosmological Attractor Models and Higher Curvature Supergravity
• Primordial perturbations from inflation with a hyperbolic field-space
• Seven-Disk Manifold, alpha-attractors and B-modes
• Multi-Natural Inflation in Supergravity and BICEP2
• Axion Inflation and Gravity Waves in String Theory
• Universality of multi-field $\alpha$-attractors
• Natural Inflation in Supergravity and Beyond
• Inflation from Nilpotent Kähler Corrections
• Is Imaginary Starobinsky Model Real?
• Power Spectra beyond the Slow Roll Approximation in Theories with Non-Canonical Kinetic Terms
• On the viability of m**2 phi**2 and natural inflation
• Supersymmetric Flaxion
• U(1) symmetric $\alpha$-attractors
• Testing Two-Field Inflation

Cited by in corpus (35)

• Swampland Distance Conjecture, Inflation and $\alpha$-attractors
• Scaling attractors in multi-field inflation
• Revisiting small-scale fluctuations in $\alpha$-attractor models of inflation
• Hybrid cosmological attractors
• Angular inflation in multi-field $\alpha$-attractors
• A manifestly covariant theory of multifield stochastic inflation in phase space: solving the discretisation ambiguity in stochastic inflation
• Revisiting non-Gaussianity in multifield inflation with curved field space
• Hyperinflation generalised: from its attractor mechanism to its tension with the `swampland conjectures'
• On preheating in alpha-attractor models of inflation
• Generating primordial features at large scales in two field models of inflation
• Polynomial $\alpha$-attractors
• On the inflationary massive field with a curved field manifold
• Attractors, Bifurcations and Curvature in Multi-field Inflation
• Universality and scaling in multi-field $\alpha$-attractor preheating
• A Tip for Landscape Riders: Multi-Field Inflation Can Fulfill the Swampland Distance Conjecture
• Dilaton-Axion Inflation with PBHs and GWs
• Pole N-flation
• Two-field Cosmological $\alpha$-attractors with Noether Symmetry
• Hidden symmetries of two-field cosmological models
• Non-oscillating Early Dark Energy and Quintessence from Alpha-Attractors
• Inflation from Multiple Pseudo-Scalar Fields: PBH Dark Matter and Gravitational Waves
• $\alpha$-attractor-type Double Inflation
• Inflaton-driven early dark energy
• Large and small field inflation from hyperbolic sigma models
• Adiabatic and isocurvature perturbations in extended theories with kinetic couplings
• Supergravity, $\alpha$-attractors and primordial non-Gaussianity
• A new take on the inflationary quintessence
• Inflation and Scale-invariant $R^2$-Gravity
• Loops in inflation with strongly non-geodesic motion
• A New Class of Non-canonical Conformal Attractors for Multifield Inflation
• Nonminimal Couplings and the Forgotten Field of Axion Inflation
• Curvature perturbations from kinetic preheating after $\alpha$-attractor inflation
• Supersymmetric Horizons at the Edge of Effective Field Theory
• Separate universe in multifield inflation: a phase-space approach
• Modification of T/E models and their multi-field versions