Primordial standing waves
File(s)
Accepted version
Author(s)
Gubitosi, Giulia
Magueijo, Joao
Type
Journal Article
Abstract
We consider the possibility that the primordial fluctuations (scalar and tensor) might have been standing waves at their moment of creation, whether or not they had a quantum origin. We lay down the general conditions for spatial translational invariance, and isolate the pieces of the most general such theory that comply with, or break translational symmetry. We find that, in order to characterize statistically translationally invariant standing waves, it is essential to consider the correlator ⟨c0(k)c0(k′)⟩ in addition to the better known ⟨c0(k)c†0(k′)⟩ [where c0(k) are the complex amplitudes of traveling waves]. We then examine how the standard process of “squeezing” (responsible for converting traveling waves into standing waves while the fluctuations are outside the horizon) reacts to being fed primordial standing waves. For translationally invariant systems only one type of standing wave, with the correct temporal phase (the “sine wave”), survives squeezing. Primordial standing waves might therefore be invisible at late times—or not—depending on their phase. Theories with modified dispersion relations behave differently in this respect, since only standing waves with the opposite temporal phase survive at late times.
Date Issued
2018-03-12
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:000427114700002&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
SQUEEZED QUANTUM STATES
INFLATION
Publication Status
Published
Article Number
ARTN 063509