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Title: Dark energy models in the w-w{sup '} plane

Abstract

We examine the behavior of dark energy models in the plane defined by w (the equation of state parameter for the dark energy) and w{sup '} (the derivative of w with respect to the logarithm of the scale factor). For nonphantom barotropic fluids with positive squared sound speed, we find that w{sup '}<3w(w+1), the opposite of the bound on quintessence models previously derived by Caldwell and Linder. Thus, these barotropic models and quintessence models for the dark energy occupy disjoint regions in the w-w{sup '} plane. We also derive two new bounds for quintessence models in the w-w{sup '} plane: the first is a general bound for any scalar field with a monotonic potential, while the second improves on the Caldwell-Linder bound for tracker quintessence models. Observationally distinguishing barotropic models from quintessence models requires {sigma}(w{sup '}) < or approx. 1+w.

Authors:
 [1]
  1. Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States)
Publication Date:
OSTI Identifier:
20776719
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevD.73.043502; (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; FLUID MECHANICS; NONLUMINOUS MATTER; POTENTIALS; SCALAR FIELDS; SOUND WAVES; VELOCITY

Citation Formats

Scherrer, Robert J. Dark energy models in the w-w{sup '} plane. United States: N. p., 2006. Web. doi:10.1103/PhysRevD.73.043502.
Scherrer, Robert J. Dark energy models in the w-w{sup '} plane. United States. doi:10.1103/PhysRevD.73.043502.
Scherrer, Robert J. Wed . "Dark energy models in the w-w{sup '} plane". United States. doi:10.1103/PhysRevD.73.043502.
@article{osti_20776719,
title = {Dark energy models in the w-w{sup '} plane},
author = {Scherrer, Robert J.},
abstractNote = {We examine the behavior of dark energy models in the plane defined by w (the equation of state parameter for the dark energy) and w{sup '} (the derivative of w with respect to the logarithm of the scale factor). For nonphantom barotropic fluids with positive squared sound speed, we find that w{sup '}<3w(w+1), the opposite of the bound on quintessence models previously derived by Caldwell and Linder. Thus, these barotropic models and quintessence models for the dark energy occupy disjoint regions in the w-w{sup '} plane. We also derive two new bounds for quintessence models in the w-w{sup '} plane: the first is a general bound for any scalar field with a monotonic potential, while the second improves on the Caldwell-Linder bound for tracker quintessence models. Observationally distinguishing barotropic models from quintessence models requires {sigma}(w{sup '}) < or approx. 1+w.},
doi = {10.1103/PhysRevD.73.043502},
journal = {Physical Review. D, Particles Fields},
number = 4,
volume = 73,
place = {United States},
year = {Wed Feb 15 00:00:00 EST 2006},
month = {Wed Feb 15 00:00:00 EST 2006}
}