Reconstructing quintom from WMAP 5-year observations: Generalized ghost
  condensate
  In the 5-year WMAP data analysis, a new parametrization form for dark energy
equation-of-state was used, and it has been shown that the equation-of-state,
$w(z)$, crosses the cosmological-constant boundary $w=-1$. Based on this
observation, in this paper, we investigate the reconstruction of quintom dark
energy model. As a single-real-scalar-field model of dark energy, the
generalized ghost condensate model provides us with a successful mechanism for
realizing the quintom-like behavior. Therefore, we reconstruct this
scalar-field quintom dark energy model from the WMAP 5-year observational
results. As a comparison, we also discuss the quintom reconstruction based on
other specific dark energy ansatzs, such as the CPL parametrization and the
holographic dark energy scenarios.
