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arXiv · 0812.0264

Anisotropic non-Gaussianity from vector field perturbations

Mindaugas Karciauskas·Konstantinos Dimopoulos·David H. Lyth
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Abstract

We suppose that a vector field perturbation causes part of the primordial curvature perturbation. The non-Gaussianity parameter fNL is then, in general, statistically anisotropic. We calculate its form and magnitude in the curvaton scenario and in the end-of-inflation scenario. We show that this anisotropy could easily be observable.

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Mindaugas Karciauskas, Konstantinos Dimopoulos, David H. Lyth. 2009-05-01. Anisotropic non-Gaussianity from vector field perturbations. https://doi.org/10.1103/physrevd.80.023509

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