2005/05/24 by R. R. Caldwell, Eric V. Linder
Physics and Astronomy · #astro-ph
paper · pdf · doi:10.1103/physrevlett.95.141301
published as Phys.Rev.Lett.95:141301,2005 · 4 pages, 2 figures
arxiv created 2005/05/24 · arxiv updated 2009/12/01
We present evidence that the simplest particle-physics scalar-field models of dynamical dark energy can be separated into distinct behaviors based on the acceleration or deceleration of the field as it evolves down its potential towards a zero minimum. We show that these models occupy narrow regions in the phase-plane of w and w', the dark energy equation-of-state and its time-derivative in units of the Hubble time. Restricting an energy scale of the dark energy microphysics limits how closely a scalar field can resemble a cosmological constant. These results, indicating a desired measurement resolution of order σ(w')≈ (1+w), define firm targets for observational tests of the physics of dark energy.