标题： 暴胀的德西特极限与非线性扰动理论 显示英文标题

标题： de Sitter limit of inflation and nonlinear perturbation theory

摘要： 我们研究暴胀宇宙中共动曲率扰动的四阶作用量，以更系统地理解非线性宇宙学扰动理论中的德西特极限。 我们推导了共动规范下曲率扰动的四阶作用量，并表明它在德西特极限下足够快地消失。 通过研究德西特极限，我们然后外推到共动曲率扰动的n阶作用量，并讨论n点关联函数的慢滚阶数。 显示英文摘要

摘要： We study the fourth order action of the comoving curvature perturbation in an inflationary universe in order to understand more systematically the de Sitter limit in nonlinear cosmological perturbation theory. We derive the action of the curvature perturbation to fourth order in the comoving gauge, and show that it vanishes sufficiently fast in the de Sitter limit. By studying the de Sitter limit, we then extrapolate to the n'th order action of the comoving curvature perturbation and discuss the slow-roll order of the n-point correlation function.