Multifield DBI Inflation and Non-Gaussianities

Abstract

We analyze the trajectories for multifield DBI inflation, which can arise in brane inflation models, and show that the trajectories are the same as in typical slow roll inflation. We calculate the power spectrum and find that the higher derivative terms of the DBI action lead to a suppression of the contribution from the isocurvature perturbations. We also calculate the bispectrum generated by the isocurvature perturbation, and find that it leads to distinctive features.

7 pages, 4 figures; v2. references added; v3. typos corrected, matches published version

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Cited by in corpus (66)

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• Riding on irrelevant operators
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• N-flation from multiple DBI type actions
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• Nonlinear perturbations of cosmological scalar fields with non-standard kinetic terms
• DBI-Curvaton
• Inflation at the Tip
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