Kinetically Driven Quintessence
نویسندگان
چکیده
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. PACS numbers: 98.80.Cq Typeset using REVTEX Electronic address: [email protected], JSPS research fellow. Electronic address: [email protected] Electronic address: [email protected], JSPS research fellow.
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