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Tracking quintessence and k-essence in a general cosmological background

Rupam Das·Thomas W. Kephart·Robert J. Scherrer
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Abstract

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.

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Rupam Das, Thomas W. Kephart, Robert J. Scherrer. 2006-09-05. Tracking quintessence and k-essence in a general cosmological background. https://doi.org/10.1103/physrevd.74.103515

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