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arXiv · 0807.0457

Boom and Bust Inflation: a Graceful Exit via Compact Extra Dimensions

Adam R. Brown
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Abstract

A model of inflation is proposed in which compact extra dimensions allow a graceful exit without recourse to flat potentials or super-Planckian field values. Though bubbles of true vacuum are too sparse to uniformly reheat the Universe by colliding with each other, a compact dimension enables a single bubble to uniformly reheat by colliding with itself. This mechanism, which generates an approximately scale invariant perturbation spectrum, requires that inflation be driven by a bulk field, that vacuum decay be slow, and that the extra dimension be at least a hundred times larger than the false vacuum Hubble length.

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Adam R. Brown. 2008-07-03. Boom and Bust Inflation: a Graceful Exit via Compact Extra Dimensions. https://doi.org/10.1103/physrevlett.101.221302

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