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arXiv · 0711.0760

DBI N-flation

John Ward
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Abstract

We investigate DBI inflation using $N$ multiple branes and show how the configuration is equivalent to a single wrapped $D5$-brane with flux. We then show how 1/N corrections can be implemented, and we examine the sound speed and levels of non-Gaussianities in two distinct cases. For models with constant warping we find that the non-Gaussian amplitude is bounded from above (as a function of $γ$). For $AdS$ backgrounds we find that the signature is generally large and positive, although is no longer globally defined over the full phase space. We then investigate an inflationary mechanism using a representation cascade, whereby the transition from a reducible representation to the irrep drives inflation.

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John Ward. 2007-11-26. DBI N-flation. https://doi.org/10.1088/1126-6708%2F2007%2F12%2F045

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