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arXiv · 1209.5742

DBI Realizations of the Pseudo-Conformal Universe and Galilean Genesis Scenarios

Kurt Hinterbichler·Austin Joyce·Justin Khoury·Godfrey E. J. Miller
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Abstract

The pseudo-conformal universe is an alternative to inflation in which the early universe is described by a conformal field theory on approximately flat space-time. The fields develop time-dependent expectation values, spontaneously breaking the conformal symmetries to a de Sitter subalgebra, and fields of conformal weight zero acquire a scale invariant spectrum of perturbations. In this paper, we show that the pseudo-conformal scenario can be naturally realized within theories that would ordinarily be of interest for DBI inflation, such as the world-volume theory of a probe brane in an AdS bulk space-time. In this approach, the weight zero spectator field can be associated with a geometric flat direction in the bulk, and its scale invariance is protected by a shift symmetry.

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Kurt Hinterbichler, Austin Joyce, Justin Khoury, Godfrey E. J. Miller. 2012-09-25. DBI Realizations of the Pseudo-Conformal Universe and Galilean Genesis Scenarios. https://doi.org/10.1088/1475-7516%2F2012%2F12%2F030

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