Primordial perturbations from multifield inflation with nonminimal couplings
Name
Kaiser-2010-Primordial perturbat.pdf
Size
147.59 KB
Format
Adobe PDF
Checksum (MD5)
7fcbfe5a75b7ad83502e07baad2e5fd2
Author(s)
Kaiser, David I.
Todhunter, Audrey T.
Date Issued
June 2010
Journal
Physical Review D
Publisher
American Physical Society
Citation
Kaiser, David I., and Audrey T. Todhunter. “Primordial perturbations from multifield inflation with nonminimal couplings.” Physical Review D 81.12 (2010): 124037. © 2010 The American Physical Society.
Version
Final published version
Abstract
Realistic models of particle physics include many scalar fields. These fields generically have nonminimal couplings to the Ricci curvature scalar, either as part of a generalized Einstein theory or as necessary counterterms for renormalization in curved background spacetimes. We develop a gauge-invariant formalism for calculating primordial perturbations in models with multiple nonminimally coupled fields. We work in the Jordan frame (in which the nonminimal couplings remain explicit) and identify two distinct sources of entropy perturbations for such models. One set of entropy perturbations arises from interactions among the multiple fields. The second set arises from the presence of nonminimal couplings. Neither of these varieties of entropy perturbations will necessarily be suppressed in the long-wavelength limit, and hence they can amplify the curvature perturbation ζ, even for modes that have crossed outside the Hubble radius. Models that overproduce long-wavelength entropy perturbations endanger the close fit between predicted inflationary spectra and empirical observations.
MIT Department
Massachusetts Institute of Technology. Center for Theoretical Physics
Massachusetts Institute of Technology. Program in Science, Technology and Society
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1103/PhysRevD.81.124037
