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arXiv · 0711.2920

Primordial Non-Gaussianity in Multi-Scalar Inflation

Shuichiro Yokoyama·Teruaki Suyama·Takahiro Tanaka
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Abstract

We give a concise formula for the non-Gaussianity of the primordial curvature perturbation generated on super-horizon scales in multi-scalar inflation model without assuming slow-roll conditions. This is an extension of our previous work. Using this formula, we study the generation of non-Gaussianity for the double inflation models in which the slow-roll conditions are temporarily violated after horizon exit, and we show that the non-linear parameter $f_{NL}$ for such models is suppressed by the slow-roll parameters evaluated at the time of horizon exit.

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Shuichiro Yokoyama, Teruaki Suyama, Takahiro Tanaka. 2007-11-19. Primordial Non-Gaussianity in Multi-Scalar Inflation. https://arxiv.org/abs/0711.2920

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