Non-Gaussianities from ekpyrotic collapse with multiple fields

Shuntaro Mizuno, Kazuya Koyama, Filippo Vernizzi, David Wands

研究成果: Conference contribution

抜粋

We compute the non-Gaussianity of the curvature perturbation generated by ekpyrotic collapse with multiple fields. The transition from the multi-field scaling solution to a single-field dominated regime converts initial isocurvature field perturbations to an almost scale-invariant comoving curvature perturbation. In the specific model of two fields, Ø1 and Ø2, with exponential potentials, -Vi exp(ciØi), we calculate the bispectrum of the resulting curvature perturbation. We find that the non-Gaussianity is dominated by non-linear evolution on super-Hubble scales and hence is of the local form. The non-linear parameter of the curvature perturbation is given by fNL = 5c2 j=12, where c j is the exponent of the potential for the field which becomes sub-dominant at late times.

元の言語English
ホスト出版物のタイトルProceedings of the 17th Workshop on General Relativity and Gravitation in Japan, JGRG 2007
ページ165-168
ページ数4
出版物ステータスPublished - 2007
外部発表Yes
イベント17th Workshop on General Relativity and Gravitation in Japan, JGRG 2007 - Nagoya
継続期間: 2007 12 32007 12 7

Other

Other17th Workshop on General Relativity and Gravitation in Japan, JGRG 2007
Nagoya
期間07/12/307/12/7

    フィンガープリント

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

これを引用

Mizuno, S., Koyama, K., Vernizzi, F., & Wands, D. (2007). Non-Gaussianities from ekpyrotic collapse with multiple fields. : Proceedings of the 17th Workshop on General Relativity and Gravitation in Japan, JGRG 2007 (pp. 165-168)