Gauge-invariant Cosmological Perturbations in Generalized Einstein Theories
نویسندگان
چکیده
Using the covariant approach and conformal transformations, we present a gauge-invariant formalism for cosmological perturbations in generalized Einstein theories (GETs), including the Brans-Dicke theory, theories with a non-minimally coupled scalar field and certain curvature-squared theories. We find an enhancement in the growth rate of density perturbations in the Brans-Dicke theory, and discuss attractive features of GETs in the structure formation process. Subject headings: cosmology: theory — galaxies: formation — relativity — large-scale structure of universe
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