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Title: w and w{sup '} of scalar field models of dark energy

Abstract

Important observables to reveal the nature of dark energy are the equation of state w and its time derivative in units of the Hubble time w{sup '}. Recently, it was shown that the simplest scalar field models of dark energy (quintessence) occupy rather narrow regions in the w-w{sup '} plane. We extend the w-w{sup '} plane to w<-1 and derive bounds on w{sup '} as a function of w for tracker phantom dark energy. We also derive bounds on tracker k-essence. The observational window for w{sup '} for w<-1 is not narrow, {sigma}(w{sup '}) < or approx. 6(1+w)

Authors:
 [1];  [2]
  1. Department of Physics, College of Humanities and Sciences, Nihon University, Tokyo 156-8550 (Japan)
  2. (Japan)
Publication Date:
OSTI Identifier:
20782605
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.73.063501; (c) 2006 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; EQUATIONS OF STATE; MATHEMATICAL MODELS; NONLUMINOUS MATTER; SCALAR FIELDS

Citation Formats

Chiba, Takeshi, and Division of Theoretical Astronomy, National Astronomical Observatory of Japan, Tokyo 181-8588. w and w{sup '} of scalar field models of dark energy. United States: N. p., 2006. Web. doi:10.1103/PHYSREVD.73.063501.
Chiba, Takeshi, & Division of Theoretical Astronomy, National Astronomical Observatory of Japan, Tokyo 181-8588. w and w{sup '} of scalar field models of dark energy. United States. doi:10.1103/PHYSREVD.73.063501.
Chiba, Takeshi, and Division of Theoretical Astronomy, National Astronomical Observatory of Japan, Tokyo 181-8588. Wed . "w and w{sup '} of scalar field models of dark energy". United States. doi:10.1103/PHYSREVD.73.063501.
@article{osti_20782605,
title = {w and w{sup '} of scalar field models of dark energy},
author = {Chiba, Takeshi and Division of Theoretical Astronomy, National Astronomical Observatory of Japan, Tokyo 181-8588},
abstractNote = {Important observables to reveal the nature of dark energy are the equation of state w and its time derivative in units of the Hubble time w{sup '}. Recently, it was shown that the simplest scalar field models of dark energy (quintessence) occupy rather narrow regions in the w-w{sup '} plane. We extend the w-w{sup '} plane to w<-1 and derive bounds on w{sup '} as a function of w for tracker phantom dark energy. We also derive bounds on tracker k-essence. The observational window for w{sup '} for w<-1 is not narrow, {sigma}(w{sup '}) < or approx. 6(1+w)},
doi = {10.1103/PHYSREVD.73.063501},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
  • No abstract prepared.
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