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Title: Direct reconstruction of the dark energy scalar-field potential

Abstract

While the accelerated expansion of the Universe is by now well established, an underlying scalar-field potential possibly responsible for this acceleration remains unconstrained. We present an attempt to reconstruct this potential using recent SN data, under the assumption that the acceleration is driven by a single scalar field. Current approaches to such reconstructions are based upon simple parametric descriptions of either the luminosity distance or the dark energy equation of state. We find that these various approximations lead to a range of derived evolutionary histories of the dark energy equation of state (although there is considerable overlap between the different potential shapes allowed by the data). Instead of these indirect reconstruction schemes, we discuss a technique to determine the potential directly from the data by expressing it in terms of a binned scalar field. We apply this technique to a recent SN data set, and compare the results with model-dependent approaches. In a similar fashion to direct estimates of the dark energy equation of state, we advocate direct reconstruction of the scalar-field potential as a way to minimize prior assumptions on the shape, and thus minimize the introduction of bias in the derived potential.

Authors:
 [1];  [2];  [3];  [4]
  1. California Institute of Technology, Mail Code 130-33, Pasadena, California 91125 (United States)
  2. Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA, and Department of Astronomy and Astrophysics, University of Chicago, Chicago, Illinois 60637 (United States)
  3. (United States)
  4. Center for Cosmology, Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States)
Publication Date:
OSTI Identifier:
20935248
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.75.103503; (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; ACCELERATION; APPROXIMATIONS; COSMOLOGICAL MODELS; EQUATIONS OF STATE; EXPANSION; NONLUMINOUS MATTER; POTENTIALS; SCALAR FIELDS; UNIVERSE

Citation Formats

Li Chao, Holz, Daniel E., Observatories of the Carnegie Institution of Washington, Pasadena, California 91101, and Cooray, Asantha. Direct reconstruction of the dark energy scalar-field potential. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.103503.
Li Chao, Holz, Daniel E., Observatories of the Carnegie Institution of Washington, Pasadena, California 91101, & Cooray, Asantha. Direct reconstruction of the dark energy scalar-field potential. United States. doi:10.1103/PHYSREVD.75.103503.
Li Chao, Holz, Daniel E., Observatories of the Carnegie Institution of Washington, Pasadena, California 91101, and Cooray, Asantha. Tue . "Direct reconstruction of the dark energy scalar-field potential". United States. doi:10.1103/PHYSREVD.75.103503.
@article{osti_20935248,
title = {Direct reconstruction of the dark energy scalar-field potential},
author = {Li Chao and Holz, Daniel E. and Observatories of the Carnegie Institution of Washington, Pasadena, California 91101 and Cooray, Asantha},
abstractNote = {While the accelerated expansion of the Universe is by now well established, an underlying scalar-field potential possibly responsible for this acceleration remains unconstrained. We present an attempt to reconstruct this potential using recent SN data, under the assumption that the acceleration is driven by a single scalar field. Current approaches to such reconstructions are based upon simple parametric descriptions of either the luminosity distance or the dark energy equation of state. We find that these various approximations lead to a range of derived evolutionary histories of the dark energy equation of state (although there is considerable overlap between the different potential shapes allowed by the data). Instead of these indirect reconstruction schemes, we discuss a technique to determine the potential directly from the data by expressing it in terms of a binned scalar field. We apply this technique to a recent SN data set, and compare the results with model-dependent approaches. In a similar fashion to direct estimates of the dark energy equation of state, we advocate direct reconstruction of the scalar-field potential as a way to minimize prior assumptions on the shape, and thus minimize the introduction of bias in the derived potential.},
doi = {10.1103/PHYSREVD.75.103503},
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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