Current constraints on the dark energy equation of state

2001/10/31 by Rachel Bean, Alessandro Melchiorri, A. Melchiorri · 6 citations
Mathematics · Physics and Astronomy · #Algorithm #Astrophysics #Black Holes and Theoretical Physics #Cosmology #Cosmology and Gravitation Theories #Current (fluid) #Dark energy #Energy (signal processing) #Equation of state #Mathematics #Physics #Quantum mechanics #Relativity and Gravitational Theory #State (computer science) #Thermodynamics #astro-ph #gr-qc #hep-th

paper · pdf · doi:10.1103/physrevd.65.041302

published as Phys.Rev. D65 (2002) 041302 · 6 pages, 6 figures. Version accepted for publication in PRD

arxiv created 2001/12/03 · openalex publication_date 2002/01/18 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

We combine complementary datasets from cosmic microwave background (CMB) anisotropy measurements, high redshift supernovae (SNIa) observations and data from local cluster abundances and galaxy clustering (LSS) to constrain the dark energy equation of state parametrized by a constant pressure-to-density ratio w_Q. Under the assumption of flatness, we find w_Q<\ensuremath-0.85 at 68% C.L., providing no significant evidence for quintessential behavior different from that of a cosmological constant. We then generalize our result to show that the constraints placed on a constant w_Q can be safely extended to dynamical theories. We consider a variety of quintessential dynamical models based on inverse power law, exponential and oscillatory scaling potentials. We find that SNIa observations are ``numbed'' to dynamical shifts in the equation of state, making the prospect of reconstructing w(z) a challenging one indeed.

Citations

• Towards a refined cosmic concordance model: Joint 11-parameter constraints from the cosmic microwave background and large-scale structure
• Phenomenology of a Realistic Accelerating Universe Using Only Planck-Scale Physics
• A Measurement of Ω from the North American Test Flight of Boomerang
• Cosmological consequences of a rolling homogeneous scalar field
• Constraining Dark Energy with Type Ia Supernovae and Large-Scale Structure

Cited by

• Inverse power law quintessence with nontracking initial conditions
• Using bright ellipticals as dark energy cosmic clocks
• Early Tracking Behavior in Small-field Quintessence Models
• Constraining cosmological parameters using Sunyaev-Zel’dovich cluster surveys
• The state of the dark energy equation of state
• The case for dynamical dark energy revisited
• Measuring the metric: A parametrized post-Friedmannian approach to the cosmic dark energy problem