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Title: Dark energy evolution and the curvature of the universe from recent observations

Abstract

We discuss the constraints on the time-varying equation of state for dark energy and the curvature of the universe using observations of type Ia supernovae from Riess et al. and the most recent Supernova Legacy Survey (SNLS), the baryon acoustic oscillation peak detected in the SDSS luminous red galaxy survey and cosmic microwave background. Because of the degeneracy among the parameters which describe the time dependence of the equation of state and the curvature of the universe, the constraints on them can be weakened when we try to constrain them simultaneously, in particular, when we use a single observational data. However, we show that we can obtain relatively severe constraints when we use all data sets from observations above even if we consider the time-varying equation of state and do not assume a flat universe. We also found that the combined data set favors a flat universe even if we consider the time variation of the dark energy equation of state.

Authors:
;  [1]
  1. Institute for Cosmic Ray Research, University of Tokyo, Kashiwa 277-8582 (Japan)
Publication Date:
OSTI Identifier:
20782897
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.73.083526; (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; BARYONS; COSMOLOGY; EQUATIONS OF STATE; NONLUMINOUS MATTER; OSCILLATIONS; RELICT RADIATION; SUPERNOVAE; TIME DEPENDENCE; UNIVERSE; VARIATIONS

Citation Formats

Ichikawa, Kazuhide, and Takahashi, Tomo. Dark energy evolution and the curvature of the universe from recent observations. United States: N. p., 2006. Web. doi:10.1103/PHYSREVD.73.083526.
Ichikawa, Kazuhide, & Takahashi, Tomo. Dark energy evolution and the curvature of the universe from recent observations. United States. doi:10.1103/PHYSREVD.73.083526.
Ichikawa, Kazuhide, and Takahashi, Tomo. Sat . "Dark energy evolution and the curvature of the universe from recent observations". United States. doi:10.1103/PHYSREVD.73.083526.
@article{osti_20782897,
title = {Dark energy evolution and the curvature of the universe from recent observations},
author = {Ichikawa, Kazuhide and Takahashi, Tomo},
abstractNote = {We discuss the constraints on the time-varying equation of state for dark energy and the curvature of the universe using observations of type Ia supernovae from Riess et al. and the most recent Supernova Legacy Survey (SNLS), the baryon acoustic oscillation peak detected in the SDSS luminous red galaxy survey and cosmic microwave background. Because of the degeneracy among the parameters which describe the time dependence of the equation of state and the curvature of the universe, the constraints on them can be weakened when we try to constrain them simultaneously, in particular, when we use a single observational data. However, we show that we can obtain relatively severe constraints when we use all data sets from observations above even if we consider the time-varying equation of state and do not assume a flat universe. We also found that the combined data set favors a flat universe even if we consider the time variation of the dark energy equation of state.},
doi = {10.1103/PHYSREVD.73.083526},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 73,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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