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arXiv · hep-th/0306113

Perturbations in a non-singular bouncing Universe

M. Gasperini·M. Giovannini·G. Veneziano
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Abstract

We complement the low-energy gravi-dilaton effective action of string theory with a non-local, general-covariant dilaton potential, and obtain homogeneous solutions describing a non-singular (bouncing-curvature) cosmology. We then compute, both analytically and numerically, the spectrum of amplified scalar and tensor perturbations, and draw some general lessons on how to extract observable consequences from pre-big bang and ekpyrotic scenarios.

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M. Gasperini, M. Giovannini, G. Veneziano. 2003-06-12. Perturbations in a non-singular bouncing Universe. https://doi.org/10.1016/j.physletb.2003.07.028

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