Curvature perturbations from kinetic preheating after $\alpha$-attractor inflation

Abstract

Preheating at the end of inflation is a violent nonlinear process that efficiently transfers the energy of the inflaton to a second field, the preheat field. When the preheat field is light during inflation and its background value modulates the preheating process, the superhorizon isocurvature perturbations of the preheat field may be converted to curvature perturbations that leave an imprint on the cosmic microwave background and the large-scale structure of the universe. We use high-precision lattice simulations to study kinetic preheating after $\alpha$-attractor inflation, a case where the effective mass of the preheat field is naturally suppressed during inflation. By comparing the expansion e-folds between different Hubble patches, we find that the conversion from isocurvature perturbations to curvature perturbations is very inefficient and can hardly be detected by cosmological observations.

MEET-U project II

References in corpus (16)

• Generating PBHs and small-scale GWs in two-field models of inflation
• Non-Gaussian Spikes from Chaotic Billiards in Inflation Preheating
• Lattice calculation of non-Gaussianity from preheating
• The Art of Lattice and Gravity Waves from Preheating
• Hybrid $\alpha$-attractors, primordial black holes and gravitational wave backgrounds
• Modulated Perturbations from Instant Preheating after new Ekpyrosis
• Cosmic Inflation at the Crossroads
• Complementing the ground-based CMB Stage-4 experiment on large scales with the PIXIE satellite
• Key drivers of the preference for dynamic dark energy
• Quantifying the tension between cosmological models and JWST red candidate massive galaxies
• Extended $\delta N$ formalism: Nonspatially Flat Separate Universe Approach
• (P)reheating and gravitational waves in $\alpha$-attractor models
• Production of gravitational waves during preheating in the Starobinsky inflationary model
• Modulated preheating and isocurvature perturbations
• High-redshift Mini-haloes from Modulated Preheating
• $\alpha$-attractor potentials in loop quantum cosmology

Cited by in corpus (1)

• Testing the cosmological principle on gigaparsec scales