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arXiv · 1102.5052

Primordial non-Gaussianities

David Langlois
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Abstract

This contribution gives an overview on primordial non-Gaussianities from a theoretical perspective. After presenting a general formalism to describe nonlinear cosmological perturbations, several classes of models, illustrated with examples, are discussed: multi-field inflation with non-standard Lagrangians, modulaton fields, curvaton fields. In the latter case, a special emphasis is put on the isocurvature perturbations, which could leave a specific signature in non-Gaussianities.

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David Langlois. 2011-02-24. Primordial non-Gaussianities. https://doi.org/10.1143/ptps.190.90

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