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arXiv · 1606.07889

Observable gravitational waves in pre-big bang cosmology: an update

M. Gasperini
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Abstract

In the light of the recent results concerning CMB observations and GW detection we address the question of whether it is possible, in a self-consistent inflationary framework, to simultaneously generate a spectrum of scalar metric perturbations in agreement with Planck data and a stochastic background of primordial gravitational radiation compatible with the design sensitivity of aLIGO/Virgo and/or eLISA. We suggest that this is possible in a string cosmology context, for a wide region of the parameter space of the so-called pre-big bang models. We also discuss the associated values of the tensor-to-scalar ratio relevant to the CMB polarization experiments. We conclude that future, cross-correlated results from CMB observations and GW detectors will be able to confirm or disprove pre-big bang models and -- in any case -- will impose new significant constraints on the basic string theory/cosmology parameters.

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M. Gasperini. 2016-06-25. Observable gravitational waves in pre-big bang cosmology: an update. https://doi.org/10.1088/1475-7516%2F2016%2F12%2F010

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