Oscillatory features in the curvature power spectrum after a sudden turn of the inflationary trajectory

Xian Gao, David Langlois, Shuntaro Mizuno

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

In the context of two-field inflation characterized by a light direction and a heavy direction, we revisit the question of the impact of the massive modes on the power spectrum produced after a turn in the inflationary trajectory. We consider in particular the resonant effect due to the background oscillations following a sharp turn. Working in the mass basis, i.e. in the basis spanned by the eigenvectors of the effective mass matrix for the perturbations, we provide an analytical estimate of the resonant effect, using the in-in formalism. In comparison with earlier estimates, we find the same the spectral dependence but a smaller amplitude. We also compute, again via the in-in formalism, the effect of the direct coupling between the light and heavy modes at the instant of the turn and confirm our previous results obtained via a different method.

Original languageEnglish
Article number023
JournalJournal of Cosmology and Astroparticle Physics
Volume2013
Issue number10
DOIs
Publication statusPublished - 2013 Oct
Externally publishedYes

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power spectra
curvature
trajectories
formalism
estimates
eigenvectors
perturbation
oscillations
matrices

Keywords

  • cosmological perturbation theory
  • inflation

ASJC Scopus subject areas

  • Astronomy and Astrophysics

Cite this

Oscillatory features in the curvature power spectrum after a sudden turn of the inflationary trajectory. / Gao, Xian; Langlois, David; Mizuno, Shuntaro.

In: Journal of Cosmology and Astroparticle Physics, Vol. 2013, No. 10, 023, 10.2013.

Research output: Contribution to journalArticle

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