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arXiv · hep-th/0610285

A Microscopic Limit on Gravitational Waves from D-brane Inflation

Daniel Baumann·Liam McAllister
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Abstract

We derive a microscopic bound on the maximal field variation of the inflaton during warped D-brane inflation. By a result of Lyth, this implies an upper limit on the amount of gravitational waves produced during inflation. We show that a detection at the level $r > 0.01$ would falsify slow roll D-brane inflation. In DBI inflation, detectable tensors may be possible in special compactifications, provided that $r$ decreases rapidly during inflation. We also show that for the special case of DBI inflation with a quadratic potential, current observational constraints imply strong upper bounds on the five-form flux.

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Daniel Baumann, Liam McAllister. 2006-10-26. A Microscopic Limit on Gravitational Waves from D-brane Inflation. https://doi.org/10.1103/physrevd.75.123508

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