Conformal frame dependence of inflation
Abstract
Physical equivalence between different conformal frames in scalartensor theory of gravity is a known fact. However, assuming that matter minimally couples to the metric of a particular frame, which we call the matter Jordan frame, the matter point of view of the universe may vary from frame to frame. Thus, there is a clear distinction between gravitational sector (curvature and scalar field) and matter sector. In this paper, focusing on a simple powerlaw inflation model in the Einstein frame, two examples are considered; a superinflationary and a bouncing universe Jordan frames. Then we consider a spectator curvaton minimally coupled to a Jordan frame, and compute its contribution to the curvature perturbation power spectrum. In these specific examples, we find a blue tilt at short scales for the superinflationary case, and a blue tilt at large scales for the bouncing case.
 Authors:
 Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 6068502 (Japan)
 Publication Date:
 OSTI Identifier:
 22525893
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 04; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CONFORMAL INVARIANCE; COSMOLOGICAL INFLATION; DISTURBANCES; GRAVITATION; INFLATIONARY UNIVERSE; METRICS; SCALAR FIELDS; SCALARS; TENSORS; UNIVERSE
Citation Formats
Domènech, Guillem, and Sasaki, Misao, Email: guillem.domenech@yukawa.kyotou.ac.jp, Email: misao@yukawa.kyotou.ac.jp. Conformal frame dependence of inflation. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/04/022.
Domènech, Guillem, & Sasaki, Misao, Email: guillem.domenech@yukawa.kyotou.ac.jp, Email: misao@yukawa.kyotou.ac.jp. Conformal frame dependence of inflation. United States. doi:10.1088/14757516/2015/04/022.
Domènech, Guillem, and Sasaki, Misao, Email: guillem.domenech@yukawa.kyotou.ac.jp, Email: misao@yukawa.kyotou.ac.jp. 2015.
"Conformal frame dependence of inflation". United States.
doi:10.1088/14757516/2015/04/022.
@article{osti_22525893,
title = {Conformal frame dependence of inflation},
author = {Domènech, Guillem and Sasaki, Misao, Email: guillem.domenech@yukawa.kyotou.ac.jp, Email: misao@yukawa.kyotou.ac.jp},
abstractNote = {Physical equivalence between different conformal frames in scalartensor theory of gravity is a known fact. However, assuming that matter minimally couples to the metric of a particular frame, which we call the matter Jordan frame, the matter point of view of the universe may vary from frame to frame. Thus, there is a clear distinction between gravitational sector (curvature and scalar field) and matter sector. In this paper, focusing on a simple powerlaw inflation model in the Einstein frame, two examples are considered; a superinflationary and a bouncing universe Jordan frames. Then we consider a spectator curvaton minimally coupled to a Jordan frame, and compute its contribution to the curvature perturbation power spectrum. In these specific examples, we find a blue tilt at short scales for the superinflationary case, and a blue tilt at large scales for the bouncing case.},
doi = {10.1088/14757516/2015/04/022},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 04,
volume = 2015,
place = {United States},
year = 2015,
month = 4
}

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