发表机构
Harvard-Smithsonian Center for Astrophysics; Laboratoire de Physique de l’École Normale Supérieure, ENS, CNRS, Université PSL, Sorbonne Université, Université Paris Cité; Tsinghua University（哈佛-史密森天体物理中心; 巴黎高等师范学院物理实验室，ENS，CNRS，PSL大学，索邦大学，巴黎西岱大学; 清华大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文利用高斯随机势模拟暴胀景观，研究单阶段与多阶段暴胀的相对出现频率，发现多阶段暴胀轨迹比例随场空间维数增加而增大，并定义了相关量以分类轨迹性质。
AI 中文摘要
暴胀景观中的一般势能通常过于陡峭，无法支持持续较长时间的宇宙暴胀。需要景观中非典型的平坦区域才能支持成功的暴胀。此类区域的出现大致导致两种可能性：单一持续较长时间的慢滚暴胀（我们称之为单阶段暴胀），或由瞬态偏离慢滚所分隔的多个较短暴胀时期（我们称之为多阶段暴胀），后者会产生原初特征及其他偏离最简慢滚模型行为的现象。前者是推导大爆炸模型原初密度涨落时最常假设的可能性。本文中，我们使用高斯随机势作为暴胀景观的简单模型，研究这两种可能性的相对出现频率。我们发现，在场空间维数为一、二和三的情况下，多阶段暴胀轨迹占据相当大比例，并且在固定典型景观曲率下，该比例随维数增加而增大。在构建暴胀景观并识别成功暴胀轨迹的过程中，我们还定义了几个相关量，并对多阶段及多场暴胀轨迹的详细性质进行了分类。
英文摘要
Generic potentials in an inflationary landscape are typically too steep to support a prolonged period of cosmic inflation. Atypical flat regions of the landscape are required to support successful inflation. The occurrence of such regions leads broadly to two possibilities: a single prolonged period of slow-roll inflation (which we call single-stage inflation), or multiple shorter periods of inflation separated by transient departures from slow roll (which we call multi-stage inflation), giving rise to primordial features and other departures from the behavior of the simplest slow-roll model. The former is the possibility most commonly assumed when deriving the primordial density fluctuations for the Big Bang model. In this paper, using Gaussian random potentials as a simple model of the inflationary landscape, we study the relative occurrence of these two possibilities. We find a substantial fraction of multi-stage inflationary trajectories in landscapes with field-space dimensions one, two, and three, and this fraction increases with dimensionality at fixed typical landscape curvature. In constructing the inflationary landscapes and identifying successful inflationary trajectories, we also define several relevant quantities and classify detailed properties of both multi-stage and multi-field inflationary trajectories.
Comments56 pages
