We compute for general single-field inflation the intrinsic non-Gaussianity due to the self-interactions of the inflaton field in the squeezed limit. We recover the consistency relation in the context of the δN formalism, and argue that there is a particular field redefinition that makes the intrinsic non-Gaussianity vanishing, thus improving the estimate of the local non-Gaussianity using the δN formalism.
|Number of pages
|Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
|Published - 10 Jun 2017
Bibliographical noteFunding Information:
We would like to thank Joey Fedrow, Antonio de Felice, Godfrey Leung, Atsushi Naruko, Ryo Saito, Yuki Sakakihara and Takahiro Tanaka for useful comments and discussions. JG acknowledges support from the Korea Ministry of Education, Science and Technology, Gyeongsangbuk-Do and Pohang City for Independent Junior Research Groups at the Asia Pacific Center for Theoretical Physics. This work is also supported in part by MEXT KAKENHI Grant Number 15H05888, by a Starting Grant through the Basic Science Research Program of the National Research Foundation of Korea (2013R1A1A1006701) and by a TJ Park Science Fellowship of POSCO TJ Park Foundation.
© 2017 The Author(s)