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Title: Quantum cosmological correlations in an inflating universe: Can fermion and gauge field loops give a scale-free spectrum?

Abstract

This paper extends the calculation of quantum corrections to the cosmological correlation <{zeta}{zeta}>, which has been done by Weinberg for a loop of minimally coupled scalars, to other types of matter loops and a general and realistic potential. It is shown here that departures from scale invariance are never large even when Dirac, vector, and conformal scalar fields are present during inflation. No fine-tuning is needed, in the sense that effective masses or coupling constants can have arbitrary values. Even when the mass is as large as M{sub Pl}, the one-loop result is still naturally smaller than the classical one. Thus, the results show that the existence of these fields during inflation may not be ruled out and is consistent with natural reheating.

Authors:
 [1]
  1. Theory Group, Department of Physics, University of Texas, Austin, Texas, 78712 (United States)
Publication Date:
OSTI Identifier:
21020146
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.75.063522; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; CONFORMAL INVARIANCE; CORRECTIONS; CORRELATIONS; COSMOLOGY; COUPLING CONSTANTS; FERMIONS; INFLATIONARY UNIVERSE; POTENTIALS; QUANTUM FIELD THEORY; SCALAR FIELDS; SCALARS; SCALE INVARIANCE; UNIVERSE; VECTORS

Citation Formats

Chaicherdsakul, Kanokkuan. Quantum cosmological correlations in an inflating universe: Can fermion and gauge field loops give a scale-free spectrum?. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.063522.
Chaicherdsakul, Kanokkuan. Quantum cosmological correlations in an inflating universe: Can fermion and gauge field loops give a scale-free spectrum?. United States. doi:10.1103/PHYSREVD.75.063522.
Chaicherdsakul, Kanokkuan. Thu . "Quantum cosmological correlations in an inflating universe: Can fermion and gauge field loops give a scale-free spectrum?". United States. doi:10.1103/PHYSREVD.75.063522.
@article{osti_21020146,
title = {Quantum cosmological correlations in an inflating universe: Can fermion and gauge field loops give a scale-free spectrum?},
author = {Chaicherdsakul, Kanokkuan},
abstractNote = {This paper extends the calculation of quantum corrections to the cosmological correlation <{zeta}{zeta}>, which has been done by Weinberg for a loop of minimally coupled scalars, to other types of matter loops and a general and realistic potential. It is shown here that departures from scale invariance are never large even when Dirac, vector, and conformal scalar fields are present during inflation. No fine-tuning is needed, in the sense that effective masses or coupling constants can have arbitrary values. Even when the mass is as large as M{sub Pl}, the one-loop result is still naturally smaller than the classical one. Thus, the results show that the existence of these fields during inflation may not be ruled out and is consistent with natural reheating.},
doi = {10.1103/PHYSREVD.75.063522},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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