Cosmological perturbations across a curvature bounce
نویسندگان
چکیده
String-inspired cosmologies, whereby a non-singular curvature bounce is induced by a general-covariant, T -duality-invariant, non-local dilaton potential, are used to study numerically how inhomogeneities evolve and to compare the outcome with analytic expressions obtained through different matching conditions across the bounce. Good agreement is found if continuity across the bounce is assumed to hold for R, the curvature perturbation on comoving hypersurfaces, rather than for the Bardeen potential. This research was supported in part by the National Science Foundation under Grant No. PHY99-07949.
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