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Title: Ups and downs of cyclic universes

Abstract

We investigate homogeneous and isotropic oscillating cosmologies with multiple fluid components. Transfer of energy between these fluids is included in order to model the effects of nonequilibrium behavior on closed universes. We find exact solutions which display a range of new behaviors for the expansion scale factor. Detailed examples are studied for the exchange of energy from dust or a scalar field into radiation. We show that, contrary to expectation, it is unlikely that such models can offer a physically viable solution to the flatness problem.

Authors:
;  [1];  [2]
  1. Department of Physics, Stanford University, Stanford, California 94305 (United States)
  2. (United Kingdom)
Publication Date:
OSTI Identifier:
21011058
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevD.75.043515; (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; COSMOLOGICAL MODELS; COSMOLOGY; EXACT SOLUTIONS; SCALAR FIELDS; UNIVERSE

Citation Formats

Clifton, T., Barrow, John D., and Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 9LN. Ups and downs of cyclic universes. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.043515.
Clifton, T., Barrow, John D., & Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 9LN. Ups and downs of cyclic universes. United States. doi:10.1103/PHYSREVD.75.043515.
Clifton, T., Barrow, John D., and Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 9LN. Thu . "Ups and downs of cyclic universes". United States. doi:10.1103/PHYSREVD.75.043515.
@article{osti_21011058,
title = {Ups and downs of cyclic universes},
author = {Clifton, T. and Barrow, John D. and Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 9LN},
abstractNote = {We investigate homogeneous and isotropic oscillating cosmologies with multiple fluid components. Transfer of energy between these fluids is included in order to model the effects of nonequilibrium behavior on closed universes. We find exact solutions which display a range of new behaviors for the expansion scale factor. Detailed examples are studied for the exchange of energy from dust or a scalar field into radiation. We show that, contrary to expectation, it is unlikely that such models can offer a physically viable solution to the flatness problem.},
doi = {10.1103/PHYSREVD.75.043515},
journal = {Physical Review. D, Particles Fields},
number = 4,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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