No Cover Image

Journal article 206 views 14 downloads

Rapid-turn inflation in supergravity is rare and tachyonic

Vikas Aragam, Roberta Chiovoloni, Sonia Paban, Robert Rosati, Ivonne Zavala Carrasco Orcid Logo

Journal of Cosmology and Astroparticle Physics, Volume: 2022, Issue: 03, Start page: 002

Swansea University Author: Ivonne Zavala Carrasco Orcid Logo

  • 61262_VoR.pdf

    PDF | Version of Record

    Copyright: 2022 The Author(s). Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence

    Download (1.46MB)

Abstract

Strongly non-geodesic, or rapidly turning trajectories in multifield inflation have attracted much interest recently from both theoretical and phenomenological perspectives. Most models with large turning rates in the literature are formulated as effective field theories. In this paper we investigat...

Full description

Published in: Journal of Cosmology and Astroparticle Physics
ISSN: 1475-7516
Published: IOP Publishing 2022
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa61262
Tags: Add Tag
No Tags, Be the first to tag this record!
Abstract: Strongly non-geodesic, or rapidly turning trajectories in multifield inflation have attracted much interest recently from both theoretical and phenomenological perspectives. Most models with large turning rates in the literature are formulated as effective field theories. In this paper we investigate rapid-turn inflation in supergravity as a first step towards understanding them in string theory. We find that large turning rates can be generated in a wide class of models, at the cost of high field space curvature. In these models, while the inflationary trajectories are stable, one Hessian eigenvalue is always tachyonic and large, in Hubble units. Thus, these models satisfy the de Sitter swampland conjecture along the inflationary trajectory. However, the high curvatures underscore the difficulty of obtaining rapid-turn inflation in realistic string-theoretical models. In passing, we revisit the η-problem in multifield slow-roll inflation and show that it does not arise, inasmuch as the inflatons, ϕi, can all be heavier (in absolute value) that the Hubble scale: |mi|/H>1, ∀i.
Keywords: inflation, string theory and cosmology, supersymmetry and cosmology
College: Faculty of Science and Engineering
Issue: 03
Start Page: 002