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Title: Possible constraints on the duration of inflationary expansion from quantum stress tensor fluctuations

Abstract

We discuss the effect of quantum stress tensor fluctuations in de Sitter spacetime upon the expansion of a congruence of timelike geodesics. We treat a model in which the expansion fluctuations begin on a given hypersurface in de Sitter spacetime, and find that this effect tends to grow, in contrast to the situation in flat spacetime. This growth potentially leads to observable consequences in inflationary cosmology in the form of density perturbations which depend upon the duration of the inflationary period. In the context of our model, the effect may be used to place upper bounds on this duration.

Authors:
; ;  [1];  [2]
  1. Institute of Physics, Academia Sinica, Nankang, Taipei 11529, Taiwan (China)
  2. (United States)
Publication Date:
OSTI Identifier:
20933287
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 10; Other Information: DOI: 10.1103/PhysRevD.75.103502; (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; COSMOLOGY; DE SITTER GROUP; EXPANSION; FLUCTUATIONS; GEODESICS; INFLATIONARY UNIVERSE; PERTURBATION THEORY; SPACE-TIME; STRESSES; TENSORS

Citation Formats

Wu, C.-H., Ng, Kin-Wang, Ford, L. H., and Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, Massachusetts 02155. Possible constraints on the duration of inflationary expansion from quantum stress tensor fluctuations. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.103502.
Wu, C.-H., Ng, Kin-Wang, Ford, L. H., & Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, Massachusetts 02155. Possible constraints on the duration of inflationary expansion from quantum stress tensor fluctuations. United States. doi:10.1103/PHYSREVD.75.103502.
Wu, C.-H., Ng, Kin-Wang, Ford, L. H., and Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, Massachusetts 02155. Tue . "Possible constraints on the duration of inflationary expansion from quantum stress tensor fluctuations". United States. doi:10.1103/PHYSREVD.75.103502.
@article{osti_20933287,
title = {Possible constraints on the duration of inflationary expansion from quantum stress tensor fluctuations},
author = {Wu, C.-H. and Ng, Kin-Wang and Ford, L. H. and Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, Massachusetts 02155},
abstractNote = {We discuss the effect of quantum stress tensor fluctuations in de Sitter spacetime upon the expansion of a congruence of timelike geodesics. We treat a model in which the expansion fluctuations begin on a given hypersurface in de Sitter spacetime, and find that this effect tends to grow, in contrast to the situation in flat spacetime. This growth potentially leads to observable consequences in inflationary cosmology in the form of density perturbations which depend upon the duration of the inflationary period. In the context of our model, the effect may be used to place upper bounds on this duration.},
doi = {10.1103/PHYSREVD.75.103502},
journal = {Physical Review. D, Particles Fields},
number = 10,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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