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arXiv · 0904.1070

The transient and the late time attractor tachyon dark energy: Can we distinguish it from quintessence ?

Amna Ali·M. Sami·A. A. Sen
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Abstract

The string inspired tachyon field can serve as a candidate of dark energy. Its equation of state parameter $w$ varies from 0 to -1. In case of tachyon field potential $V(ϕ)\to 0$ slower(faster) than $1/ϕ^2$ at infinity, dark energy(dark matter) is a late time attractor. We investigate the tachyon dark energy models under the assumption that $w$ is close to -1. We find that all the models exhibit unique behavior around the present epoch which is exactly same as that of the thawing quintessence.

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Amna Ali, M. Sami, A. A. Sen. 2009-05-15. The transient and the late time attractor tachyon dark energy: Can we distinguish it from quintessence ?. https://doi.org/10.1103/physrevd.79.123501

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