论文标题
小规模结构对宇宙弦的重力波的随机背景的影响
Impact of the small-scale structure on the Stochastic Background of Gravitational Waves from cosmic strings
论文作者
论文摘要
数值模拟和分析模型表明，无限的宇宙弦线与给定的幂律产生各种尺寸的宇宙弦乐环。幂律指数的精确估计仍然是争论的问题，而数值模拟并未结合预期在小尺度上影响网络的所有辐射和后反应效应。以前，使用玻尔兹曼方法表明，取决于环路生产函数的陡度和重力反反应量表，可以在环数密度中生成所谓的额外小环（EPSL）。我们提出了一个框架，以研究这种额外的小环对重力波（SBGW）随机背景的影响。我们表明，这种额外的人口可以具有高于$ h_0（γgμ）^{ - 1} $的频率的显着签名，其中$γ$属于$ 50 $，$ h_0 $是哈勃常数。我们提出了从宇宙弦到四个类别的重力波功率光谱的完整分类，包括Blanco-Pillado，Olum和Shlaer的模型以及Lorenz，Ringeval和Sakellarariadou的模型。最后，我们表明，鉴于Polchinski-Rocha指数的不确定性，可以认为两种杂交引力波功率谱对SBGW给出截然不同的预测。
Numerical simulations and analytical models suggest that infinite cosmic strings produce cosmic string loops of all sizes with a given power-law. Precise estimations of the power-law exponent are still matter of debate while numerical simulations do not incorporate all the radiation and back-reaction effects expected to affect the network at small scales. Previously it has been shown, using a Boltzmann approach, that depending on the steepness of the loop production function and the gravitational back-reaction scale, a so-called Extra Population of Small Loops (EPSL) can be generated in the loop number density. We propose a framework to study the influence of this extra population of small loops on the Stochastic Background of Gravitational Waves (SBGW). We show that this extra population can have a significant signature at frequencies higher than $H_0(ΓGμ)^{-1}$ where $Γ$ is of order $50$ and $H_0$ is the Hubble constant. We propose a complete classification of the gravitational wave power spectra expected from cosmic strings into four classes, including the model of Blanco-Pillado, Olum and Shlaer and the model of Lorenz, Ringeval and Sakellariadou. Finally we show that given the uncertainties on the Polchinski-Rocha exponents, two hybrid classes of gravitational wave power spectrum can be considered giving very different predictions for the SBGW.
