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arXiv · 1004.1776

Trispectrum from Ghost Inflation

Keisuke Izumi·Shinji Mukohyama
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Abstract

Ghost inflation predicts almost scale-invariant primordial cosmological perturbations with relatively large non-Gaussianity. The bispectrum is known to have a large contribution at the wavenumbers forming an equilateral triangle and the corresponding nonlinear parameter $f_{NL}^{equil}$ is typically of order $O(10^2)$. In this paper we calculate trispectrum from ghost inflation and show that the corresponding nonlinear parameter $\tau_{NL}$ is typically of order $O(10^4)$. We investigate the shape dependence of the trispectrum and see that it has some features different from DBI inflation. Therefore, our result may be useful as a template to distinguish ghost inflation from other models of inflation by future experiments.

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Keisuke Izumi, Shinji Mukohyama. 2010-04-11. Trispectrum from Ghost Inflation. https://doi.org/10.1088/1475-7516/2010/06/016

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