arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2002.11083astro-ph.COgr-qchep-ph
收藏

密度扰动对引力波谱的影响

Deformation of the gravitational wave spectrum by density perturbations

Valerie Domcke, Ryusuke Jinno, Henrique Rubira

备注：
30 pages, 8 figures; figure 3 replaced in v2; JCAP published version in v3
阅读 PDF
arXiv 页面 ↗HTML 原文 ↗

摘要：

研究了原初标量曲率扰动对宇宙距离上引力波传播的影响。我们指出，这种曲率扰动变形的任何随机背景的引力波的原始起源通过（集成）萨克斯-沃尔夫效应的各向同性频谱。通过计算标量曲率扰动引起的线性阶传播引力波的振幅和频率的变化，证明了引力波频谱中每个频点的形变可用方差为$σ^2 \simeq \int d\ln k Δ_{\mathcal R}^2$的线性偏置高斯描述，其中$Δ_{\mathcal R}^2(k)$表示原始曲率扰动的振幅.线性偏置编码了引力波的频率和振幅变化之间的相关性。考虑到原始黑洞和引力波搜索的$Δ_{\mathcal R}^2$的最新边界，我们证明了由此产生的${\mathcal O}(σ)$变形对于极端峰值的引力波谱是显著的。我们进一步提供了一个数量级估计宽谱，其中净失真是${\mathcal O}(σ^2)$。

英文摘要：

We study the effect of primordial scalar curvature perturbations on the propagation of gravitational waves over cosmic distances. We point out that such curvature perturbations deform the isotropic spectrum of any stochastic background of gravitational waves of primordial origin through the (integrated) Sachs-Wolfe effect. Computing the changes in the amplitude and frequency of the propagating gravitational wave induced at linear order by scalar curvature perturbations, we show that the resulting deformation of each frequency bin of the gravitational wave spectrum is described by a linearly biased Gaussian with the variance $σ^2 \simeq \int d\ln k Δ_{\mathcal R}^2$, where $Δ_{\mathcal R}^2(k)$ denotes the amplitude of the primordial curvature perturbations. The linear bias encodes the correlations between the changes induced in the frequency and amplitude of the gravitational waves. Taking into account the latest bounds on $Δ_{\mathcal R}^2$ from primordial black hole and gravitational wave searches, we demonstrate that the resulting ${\mathcal O}(σ)$ deformation can be significant for extremely peaked gravitational wave spectra. We further provide an order of magnitude estimate for broad spectra, for which the net distortion is ${\mathcal O}(σ^2)$.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

↑