HD - THEP - 00 - 38 August 2000 Natural Quintessence ?
نویسندگان
چکیده
We formulate conditions for the naturalness of cosmological quintessence scenarios. The quintessence lagrangian is taken to be the sum of a simple exponential potential and a non-canonical kinetic term. This parameterization covers most variants of quintessence and makes the naturalness conditions particularly transparent. Several " natural " scalar models lead, for the present cosmological era, to a large fraction of homogeneous dark energy density and an acceleration of the scale factor as suggested by observation.
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