Abstract
By combining data from seven cosmic microwave background experiments (including the latest WMAP results) with the Hubble parameter measurement from the Hubble space telescope and luminosity measurements of type Ia supernovae, we demonstrate the bounds on the dark energy equation of state to be at the 95% confidence level. Although our limit on is improved with respect to previous analyses, cosmological data do not rule out the possibility that the equation of state parameter of the dark energy Q is less than We present a tracking model that ensures at recent times and discuss the observational consequences.
- Received 6 December 2002
DOI:https://doi.org/10.1103/PhysRevD.68.043509
©2003 American Physical Society