Scale invariance in expanding and contracting universes from two-field models
نویسندگان
چکیده
منابع مشابه
Scale-invariance in expanding and contracting universes from two-field models
We study cosmological perturbations produced by the most general twoderivative actions involving two scalar fields, coupled to Einstein gravity, with an arbitrary field space metric, that admit scaling solutions. For expanding universes, we find that scaleinvariant adiabatic perturbation spectra can be produced for any equation of state parameter w that satisfies −1 ≤ w < −1/3, and that all the...
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ژورنال
عنوان ژورنال: Journal of Cosmology and Astroparticle Physics
سال: 2007
ISSN: 1475-7516
DOI: 10.1088/1475-7516/2007/05/006