Document Type

Article

Publication Date

3-7-2002

Publication Title

Physical Review Letters

Department

Department of Physics and Astronomy

Abstract

Quintessence, a time-varying energy component that may account for the accelerated expansion of the universe, can be characterized by its equation of state and sound speed. In this paper, we show that if the quintessence density is at least 1% of the critical density at the surface of last scattering the cosmic microwave background anisotropy can distinguish between models whose sound speed is near the speed of light versus near zero, which could be useful in distinguishing competing candidates for dark energy.

DOI

10.1103/PhysRevLett.88.121301

Download
COinS