Inflation in DBI models with constant gamma

Michal Spalinski

doi:10.1088/1475-7516/2008/04/002

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arXiv · 0711.4326

Inflation in DBI models with constant gamma

Michal Spalinski

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Abstract

Dirac-Born-Infeld scalar field theories which appear in the context of inflation in string theory in general have a field dependent speed of sound. It is however possible to write down DBI models which possess exact solutions characterized by a constant speed of sound different from unity. This requires that the potential and the effective D-brane tension appearing in a DBI action have to be related in a specific way. This paper describes such models in general and presents some examples with a constant speed of sound $c_s<1$ for which the spectrum of scalar perturbations can be found analytically without resorting to the slow roll approximation.

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Michal Spalinski. 2008-04-14. Inflation in DBI models with constant gamma. https://doi.org/10.1088/1475-7516%2F2008%2F04%2F002

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