Squeezing of scalar and tensor primordial perturbations generated by modified dispersion relations
File(s)
Accepted version
Author(s)
Gubitosi, Giulia
Magueijo, Joao
Type
Journal Article
Abstract
In recent work we analyzed the evolution of primordial perturbations satisfying Planck-scale-modified dispersion relations and showed that there is no cosmological “squeezing” in the critical model that produces perturbations with a scale invariant spectrum. Nevertheless, the perturbations reenter the horizon as standing waves with the correct temporal phase because of the late-time decay of the momentum mode. Here we shed light on the absence of primordial squeezing by reexamining the problem in the dual rainbow frame, where c is set to 1, shifting the varying c effects elsewhere. In this frame gravity switches off at sub-Planckian wavelengths, so that the fluctuations behave as if they were in Minkowski spacetime. This is ultimately why they are not squeezed. However, away from the critical model squeezing does occur if the fluctuations spectrum is red, as is the case for scalar perturbations. Should the primordial gravity waves have a blue spectrum, we predict that they might not reenter the horizon as standing waves, because the momentum mode would be enhanced in the primordial phase.
Date Issued
2018-03-02
Date Acceptance
2018-03-01
Citation
PHYSICAL REVIEW D, 2018, 97 (6)
ISSN
2470-0010
Publisher
American Physical Society
Journal / Book Title
PHYSICAL REVIEW D
Volume
97
Issue
6
Copyright Statement
© 2018 American Physical Society
Sponsor
Science and Technology Facilities Council (STFC)
John Templeton Foundation
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000426527100003&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Grant Number
ST/L00044X/1
ID#47633
Subjects
Science & Technology
Physical Sciences
Astronomy & Astrophysics
Physics, Particles & Fields
Physics
COSMOLOGICAL PERTURBATIONS
Publication Status
Published
Article Number
ARTN 063502