Curvature perturbations from vacuum transition during inflation
File(s)
Published version
Author(s)
Garbrecht, Bjoern
Ghoderao, Pulkit S
Rajantie, Arttu
Type
Journal Article
Abstract
We demonstrate that in the presence of a light scalar spectator field, vacuum transitions taking place during inflation can produce large, potentially detectable non-Gaussian signatures in the primordial curvature perturbation. Such transitions are common in theories with multiple scalar fields when the potential has several minima. Our computation proceeds by numerically finding the instanton solution that describes quantum tunnelling between vacuum states in a de Sitter background, calculating its dependence on the spectator field and, thereby, its effect on the expansion of space. For a scenario with Higgs inflation, we obtain the non-Gaussianity parameter fNL ∼ O(10) and study its parameter dependence.
Date Issued
2025-05-01
Date Acceptance
2025-04-07
Citation
Journal of Cosmology and Astroparticle Physics, 2025, 2025 (5)
ISSN
1475-7516
Publisher
IOP Publishing
Journal / Book Title
Journal of Cosmology and Astroparticle Physics
Volume
2025
Issue
5
Copyright Statement
© 2025 The Author(s). Published by IOP Publishing Ltd on behalf of Sissa Medialab. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
License URL
Subjects
Astronomy & Astrophysics
BUBBLE NUCLEATION
cosmological phase transitions
EVOLUTION
FALSE VACUUM
FATE
FLATNESS
FLUCTUATIONS
HORIZON
inflation
non-gaussianity
Physical Sciences
Physics
Physics, Particles & Fields
Quantum fields in curved spacetimes
Science & Technology
UNIVERSE
Publication Status
Published
Article Number
049
Date Publish Online
2025-05-20