English

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

Cosmology and Nongalactic Astrophysics 2011-06-02 v1 General Relativity and Quantum Cosmology High Energy Physics - Phenomenology High Energy Physics - Theory

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.

Keywords

Cite

@article{arxiv.1009.1979,
  title  = {On Classification of Models of Large Local-Type Non-Gaussianity},
  author = {Teruaki Suyama and Tomo Takahashi and Masahide Yamaguchi and Shuichiro Yokoyama},
  journal= {arXiv preprint arXiv:1009.1979},
  year   = {2011}
}

Comments

67 pages, 6 figures