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arXiv · hep-th/0406098

Heating up the cold bounce

Massimo Giovannini
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Abstract

Self-dual string cosmological models provide an effective example of bouncing solutions where a phase of accelerated contraction smoothly evolves into an epoch of decelerated Friedmann--Robertson--Walker expansion dominated by the dilaton. While the transition to the expanding regime occurs at sub-Planckian curvature scales, the Universe emerging after the bounce is cold, with sharply growing gauge coupling. However, since massless gauge bosons (as well as other massless fields) are super-adiabatically amplified, the energy density of the maximally amplified modes re-entering the horizon after the bounce can efficiently heat the Universe. As a consequence the gauge coupling reaches a constant value, which can still be perturbative.

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Massimo Giovannini. 2004-06-11. Heating up the cold bounce. https://doi.org/10.1088/0264-9381%2F21%2F17%2F010

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