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arXiv · 1002.3110

Review of local non-Gaussianity from multi-field inflation

Christian T. Byrnes·Ki-Young Choi
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Abstract

We review models which generate a large non-Gaussianity of the local form. We first briefly consider three models which generate the non-Gaussianity either at or after the end of inflation; the curvaton scenario, modulated (p)reheating and an inhomogeneous end of inflation. We then focus on ways of generating the non-Gaussianity during inflation. We derive general conditions which a product or sum separable potential must satisfy in order to generate a large local bispectrum during slow-roll inflation. As an application we consider two-field hybrid inflation. We then derive a formalism not based on slow roll which can be applied to models in which the slow-roll parameters become large before inflation ends. An exactly soluble two-field model is given in which this happens. Finally we also consider further non-Gaussian observables; a scale dependence of f_NL and the trispectrum.

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Christian T. Byrnes, Ki-Young Choi. 2010-04-29. Review of local non-Gaussianity from multi-field inflation. https://doi.org/10.1155/2010%2F724525

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