General analytic formulas for attractor solutions of scalar-field dark energy models and their multifield generalizations

2006/01/31 by Shinji Tsujikawa · 3 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Solar and Space Plasma Dynamics #astro-ph #gr-qc #hep-ph #hep-th

paper · pdf · doi:10.1103/physrevd.73.103504

published as Phys.Rev.D73:103504,2006 · 11 pages, no figures, version to appear in Physical Review D

arxiv created 2006/05/01 · openalex publication_date 2006/05/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28

Abstract

We study general properties of attractors for scalar-field dark energy scenarios which possess cosmological scaling solutions. In all such models there exists a scalar-field dominant solution with an energy fraction \ensuremathΩ_\ensuremathφ=1 together with a scaling solution. A general analytic formula is given to derive fixed points relevant to dark energy coupled to dark matter. We investigate the stability of fixed points without specifying the models of dark energy in the presence of nonrelativistic dark matter and provide a general proof that a nonphantom scalar-field dominant solution is unstable when a stable scaling solution exists in the region \ensuremathΩ_\ensuremathφ<1. A phantom scalar-field dominant fixed point is found to be classically stable. We also generalize the analysis to the case of multiple scalar fields and show that for a nonphantom scalar-field assisted acceleration always occurs for all scalar-field models which have scaling solutions. For a phantom field the equation of state approaches that of cosmological constant as we add more scalar fields.

Citations

• Cosmological Constant - the Weight of the Vacuum
• The classical stability of the ghost condensate
• Cosmological scaling solutions and cross-coupling exponential potential
• Classification of scalar field potentials with cosmological scaling solutions
• Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant
• A theoretician's analysis of the supernova data and the limitations in determining the nature of dark energy
• Cosmological parameter analysis including SDSS Lyαforest and galaxy bias: Constraints on the primordial spectrum of fluctuations, neutrino mass, and dark energy
• Foundations of observing dark energy dynamics with the Wilkinson Microwave Anisotropy Probe
• Cosmological consequences of a rolling homogeneous scalar field
• The Case for a Positive Cosmological Lambda-term

Cited by

• Multiple kinetic k-essence, phantom barrier crossing and stability
• The generalized second law in irreversible thermodynamics for the interacting dark energy in a non-flat FRW universe enclosed by the apparent horizon
• The generalized second law of gravitational thermodynamics on the apparent and event horizons in FRW cosmology