Loop quantum cosmology and the k=1 RobertsonWalker model
Abstract
The loop quantization of the negatively curved k=1 RobertsonWalker model poses several technical challenges. We show that the issues can be overcome and a successful quantization is possible that extends the results of the k=0, +1 models in a natural fashion. We discuss the resulting dynamics and show that for a universe consisting of a massless scalar field, a bounce is predicted in the backward evolution in accordance with the results of the k=0, +1 models. We also show that the model predicts a vacuum repulsion in the high curvature regime that would lead to a bounce even for matter with vanishing energy density. We finally comment on the inverse volume modifications of loop quantum cosmology and show that, as in the k=0 model, the modifications depend sensitively on the introduction of a length scale which a priori is independent of the curvature scale or a matter energy scale.
 Authors:
 Institute for Gravitational Physics and Geometry, Pennsylvania State University, University Park, Pennsylvania 16802 (United States)
 (United Kingdom)
 Publication Date:
 OSTI Identifier:
 20935219
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevD.75.023523; (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; ENERGY DENSITY; GALACTIC EVOLUTION; MATTER; QUANTIZATION; QUANTUM GRAVITY; SCALAR FIELDS; UNIVERSE
Citation Formats
Vandersloot, Kevin, and Institute for Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 2EG. Loop quantum cosmology and the k=1 RobertsonWalker model. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.023523.
Vandersloot, Kevin, & Institute for Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 2EG. Loop quantum cosmology and the k=1 RobertsonWalker model. United States. doi:10.1103/PHYSREVD.75.023523.
Vandersloot, Kevin, and Institute for Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 2EG. Mon .
"Loop quantum cosmology and the k=1 RobertsonWalker model". United States.
doi:10.1103/PHYSREVD.75.023523.
@article{osti_20935219,
title = {Loop quantum cosmology and the k=1 RobertsonWalker model},
author = {Vandersloot, Kevin and Institute for Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 2EG},
abstractNote = {The loop quantization of the negatively curved k=1 RobertsonWalker model poses several technical challenges. We show that the issues can be overcome and a successful quantization is possible that extends the results of the k=0, +1 models in a natural fashion. We discuss the resulting dynamics and show that for a universe consisting of a massless scalar field, a bounce is predicted in the backward evolution in accordance with the results of the k=0, +1 models. We also show that the model predicts a vacuum repulsion in the high curvature regime that would lead to a bounce even for matter with vanishing energy density. We finally comment on the inverse volume modifications of loop quantum cosmology and show that, as in the k=0 model, the modifications depend sensitively on the introduction of a length scale which a priori is independent of the curvature scale or a matter energy scale.},
doi = {10.1103/PHYSREVD.75.023523},
journal = {Physical Review. D, Particles Fields},
number = 2,
volume = 75,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}

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