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arXiv · astro-ph/9912463

Kinetically Driven Quintessence

Takeshi Chiba·Takahiro Okabe·Masahide Yamaguchi
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Abstract

Recently, a novel class of models for inflation has been found in which the inflationary dynamics is driven solely by (non-canonical) kinetic terms rather than by potential terms. As an obvious extension, we show that a scalar field with non-canonical kinetic terms alone behaves like an energy component which is time-varying and has negative pressure presently, i.e. quintessence. We present a model which has a constant equation of state, that is, a ``kinetic'' counterpart of the Ratra-Peebles model of a quintessence field with a potential term. We make clear the structure of the phase plane and show that the quintessential solution is a late-time attractor. We also give a model for the ``phantom'' component which has an equation of state with $w=p/ρ<-1$.

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Takeshi Chiba, Takahiro Okabe, Masahide Yamaguchi. 2000-01-29. Kinetically Driven Quintessence. https://doi.org/10.1103/physrevd.62.023511

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