摘要
在精确宇宙学的时代,多信使、高精度、小尺度的宇宙学观测在帮助人们从更加深刻的层面理解宇宙极早期的同时,也给基于线性近似和微扰展开宇宙学扰动理论带来了新的挑战.近年来,对原初引力波和原初黑洞的搜寻使得研究人员们对早期宇宙在小尺度上的非线性非微扰过程产生了浓厚的研究兴趣.综述了在宇宙学小尺度上关于原初黑洞产生以及引力波研究取得的诸多进展,重点关注了使用Mathieu方程的共振效应来研究小尺度功率谱放大以及诱导产生可观测的原初引力波的方法.此外,还尝试探讨了非高斯尾巴对原初黑洞形成的影响.发现Mathieu方程所具备的共振效应可以提供一种有效的方法来刻画原初宇宙中小尺度的非微扰动力学过程,从而能够更好地理解原初黑洞的形成以及相关的引力波产生机制.同时,非微扰的非高斯性在原初黑洞形成中可能会产生不可忽视的影响.
In the era of precision cosmology,multi-messenger,high-resolution as well as small-scale cosmological observations have provided profound insights into the early universe,while also presenting new challenges to cosmological perturbation theory based on linear approximation and perturbative ex-pansions.In recent years,the search for primordial gravitational waves and primordial black holes has generated significant research interest in the non-linear and non-perturbative processes in the early u-niverse at small scales.This review paper summarizes the progress in understanding the generation of primordial black holes and gravitational waves at cosmological small scales.Specifically,we focus on the application of the resonance effect depicted by the Mathieu equation to study small-scale power spectrum amplification and the induction of observable primordial gravitational waves.Furthermore,we attempt to explore the influence of non-Gaussian tails on primordial black hole formation.Ourfindings indicate that the resonance effect of the Mathieu equation provides an effective approach to describe non-perturbative and non-linear processes at small scales in the early universe,leading to a better understanding of the mechanisms behind primordial black hole formation and gravitational wave generation.Additionally,the non-perturbative non-Gaussianity may have a significant impact on the formation of primordial black holes.
作者
蔡一夫
何鑫宸
马潇汉
CAI Yi-fu;HE Xin-chen;MA Xiao-han(School of Astronomy and Space Science,University of Science and Technology of China,Hefei 230026;Deep Space Exploration Laboratory/Department of Astronomy,School of Physical Sciences,University of Science and Technology of China,Hefei 230026)
出处
《天文学报》
CAS
CSCD
北大核心
2024年第3期1-27,共27页
Acta Astronomica Sinica
基金
科技部国家重点研发计划(2021YFC2203100)
国家自然科学基金项目(12261131497)
中国科学院青年交叉团队项目(JCTD-2022-20)
中国科学院基础研究领域青年团队项目(YSBR-006)资助
111基地项目(B23042)。
关键词
宇宙学:暴胀理论
早期宇宙
原初引力波
非高斯性
原初黑洞
cosmology:inflation
early universe
primordial gravitational waves
non-Gaussianity
pri-mordial black holes
