Strong scale dependent bispectrum in the Starobinsky model of inflation

Дата и время публикации : 2012-04-29T15:55:44Z

Авторы публикации и институты :
Frederico Arroja
Misao Sasaki

Ссылка на журнал-издание: JCAP 1208 (2012) 012
Коментарии к cтатье: 14 pages, 3 figures
Первичная категория: astro-ph.CO

Все категории : astro-ph.CO, gr-qc, hep-th

Краткий обзор статьи: We compute analytically the dominant contribution to the tree-level bispectrum in the Starobinsky model of inflation. In this model, the potential is vacuum energy dominated but contains a subdominant linear term which changes the slope abruptly at a point. We show that on large scales compared with the transition scale $k_0$ and in the equilateral limit the analogue of the non-linearity parameter scales as $(k/k_0)^2$, that is its amplitude decays for larger and larger scales until it becomes subdominant with respect to the usual slow-roll suppressed corrections. On small scales we show that the non-linearity parameter oscillates with angular frequency given by $3/k_0$ and its amplitude grows linearly towards smaller scales and can be large depending on the model parameters. We also compare our results with previous results in the literature.

Category: Physics