Induced Gravity and the Attractor Dynamics of Dark Energy/Dark Matter

Journal of Cosmology and Astroparticle Physics (Impact Factor: 5.88). 10/2010; DOI: 10.1088/1475-7516/2010/12/019
Source: arXiv

ABSTRACT Attractor solutions that give dynamical reasons for dark energy to act like the cosmological constant, or behavior close to it, are interesting possibilities to explain cosmic acceleration. Coupling the scalar field to matter or to gravity enlarges the dynamical behavior; we consider both couplings together, which can ameliorate some problems for each individually. Such theories have also been proposed in a Higgs-like fashion to induce gravity and unify dark energy and dark matter origins. We explore restrictions on such theories due to their dynamical behavior compared to observations of the cosmic expansion. Quartic potentials in particular have viable stability properties and asymptotically approach general relativity. Comment: 11 pages, 10 figures

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