PIRSA:08060140  ( MP4 Medium Res , MP3 , PDF ) Which Format?
Monodromy in the CMB: Gravity Waves and String Inflation
Speaker(s): Alexander Westphal
Abstract: We present a simple mechanism for obtaining large-field inflation, and hence a gravitational wave signature, from string theory compactified on twisted tori. For Nil manifolds, we obtain a leading inflationary potential proportional to phi^(2/3) in terms of the canonically normalized field phi, yielding predictions for the tilt of the power spectrum and the tensor-to-scalar ratio, $n_sapprox 0.98$ and $rapprox 0.04$ with 60 e-foldings of inflation; we note also the possibility of a variant with a candidate inflaton potential proportional to phi^(2/5). The basic mechanism involved in extending the field range -- monodromy in D-branes as they move in circles on the manifold -- arises in a more general class of compactifications, though our methods for controlling the corrections to the slow-roll parameters require additional symmetries.
Date: 03/06/2008 - 5:00 pm
Collection: PASCOS 08
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