Non-Gaussianities in multifield DBI inflation with a waterfall phase transition

Taichi Kidani, Kazuya Koyama, Shuntaro Mizuno

研究成果: Article査読

10 被引用数 (Scopus)


We study multifield Dirac-Born-Infeld (DBI) inflation models with a waterfall phase transition. This transition happens for a D3 brane moving in the warped conifold if there is an instability along angular directions. The transition converts the angular perturbations into the curvature perturbation. Thanks to this conversion, multifield models can evade the stringent constraints that strongly disfavor single field ultraviolet (UV) DBI inflation models in string theory. We explicitly demonstrate that our model satisfies current observational constraints on the spectral index and equilateral non-Gaussianity as well as the bound on the tensor to scalar ratio imposed in string theory models. In addition, we show that large local type non-Gaussianity is generated together with equilateral non-Gaussianity in this model.

ジャーナルPhysical Review D - Particles, Fields, Gravitation and Cosmology
出版ステータスPublished - 2012 10 1

ASJC Scopus subject areas

  • Nuclear and High Energy Physics

フィンガープリント 「Non-Gaussianities in multifield DBI inflation with a waterfall phase transition」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。