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arXiv · 1009.1979

On Classification of Models of Large Local-Type Non-Gaussianity

Teruaki Suyama·Tomo Takahashi·Masahide Yamaguchi·Shuichiro Yokoyama
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Abstract

We classify models generating large local-type non-Gaussianity into some categories by using some "consistency relations" among the non-linearity parameters f_{NL}^{local}, \tau_{NL}^{local} and g_{NL}^{local}, which characterize the size of bispectrum for the former and trispectrum for the later two. Then we discuss how one can discriminate models of large local-type non-Gaussianity with such relations. We first classify the models by using the ratio of \tau_{NL}^{local}/(6f_{NL}^{local}/5)^2, which is unity for "single-source" models and deviates from unity for "multi-source" ones. We can make a further classification of models in each category by utilizing the relation between f_{NL}^{local} and g_{NL}^{local}. Our classification suggests that observations of trispectrum would be very helpful to distinguish models of large non-Gaussianity and may reveal the generation mechanism of primordial fluctuations.

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Teruaki Suyama, Tomo Takahashi, Masahide Yamaguchi, Shuichiro Yokoyama. 2010-09-10. On Classification of Models of Large Local-Type Non-Gaussianity. https://doi.org/10.1088/1475-7516/2010/12/030

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