On the Evolution of Scalar Metric Perturbations in an Innationary Cosmology
نویسنده
چکیده
We further clarify how scalar metric perturbations are ampliied in an innationary cosmology. We rst construct a simple, analytic model of an in-ationary cosmology in which the expansion scale factor evolves continuously from an innationary era to a radiation-dominated era. From this model, it is clear to see how scalar perturbations are ampliied. Second, we examine the recent claims of Grishchuk, and the reply by Deruelle and Mukhanov, regarding the evolution of scalar perturbations through an abrupt transition in the equation of state of the cosmological uid. We demonstrate that the \standard results" regarding the ampliication of scalar, density perturbations from innation are valid.
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