Tracking quintessence and k-essence in a general cosmological background

Das, Rupam; Kephart, Thomas W.; Scherrer, Robert J.

Tracking quintessence and k-essence in a general cosmological background

Authors

Das, Rupam

Kephart, Thomas W.

Scherrer, Robert J.

Description

We derive conditions for stable tracker solutions for both quintessence and k-essence in a general cosmological background, H^2 \propto f(ρ). We find that tracker solutions are possible only when η= d ln f /d ln ρis constant, aside from a few special cases, which are enumerated. Expressions for the quintessence or k-essence equation of state are derived as a function of ηand the equation of state of the dominant background component.
6 pages, no figures