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arXiv · 0911.3380

Quasi-Single Field Inflation and Non-Gaussianities

Xingang Chen·Yi Wang
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Abstract

In quasi-single field inflation models, massive isocurvature modes, that are coupled to the inflaton and have mass of order the Hubble parameter, can have nontrivial impacts on density perturbations, especially non-Gaussianities. We study a simple example of quasi-single field inflation in terms of turning inflaton trajectory. Large bispectra with a one-parameter family of novel shapes arise, lying between the well-known local and equilateral shape. The trispectra can also be very large and its magnitude tNL can be much larger than fNL squared.

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Xingang Chen, Yi Wang. 2010-04-24. Quasi-Single Field Inflation and Non-Gaussianities. https://doi.org/10.1088/1475-7516/2010/04/027

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