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arXiv · 1003.2869

Gravity and non-gravity mediated couplings in multiple-field inflation

Francis Bernardeau
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Abstract

Mechanisms for the generation of primordial non-Gaussian metric fluctuations in the context of multiple-field inflation are reviewed. As long as kinetic terms remain canonical, it appears that nonlinear couplings inducing non-gaussianities can be split into two types. The extension of the one-field results to multiple degrees of freedom leads to gravity mediated couplings that are ubiquitous but generally modest. Multiple-field inflation offers however the possibility of generating non-gravity mediated coupling in isocurvature directions that can eventually induce large non-Gaussianities in the metric fluctuations. The robustness of the predictions of such models is eventually examined in view of a case study derived from a high-energy physics construction.

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Francis Bernardeau. 2010-03-15. Gravity and non-gravity mediated couplings in multiple-field inflation. https://doi.org/10.1088/0264-9381%2F27%2F12%2F124004

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