论文标题
一般相对论的星系功率谱
Galaxy Power Spectrum in General Relativity
论文作者
论文摘要
我们介绍了一般相对论的星系功率谱。使用一种新颖的方法，我们可以考虑到观察结果中所有相对论效应的星系功率谱。特别是，我们独立于调查几何形状表明，相对论效应没有发散的术语（与$ k^{ - 4} p_m（k）$或$ k^{ - 2} p_m（k）$在所有尺度上都可以模仿原始非高斯非高斯的信号。这种分歧术语的这种取消确实可以从等价原理中预期，这意味着任何在实验规模上充当均匀重力的扰动都无法测量。我们发现，在以前的计算中获得的非物理红外差异仅由于不始终如一地考虑所有一般相对论贡献而发生。尽管没有发散的术语，但以非发散术语表示的一般相对论效应会在大尺度上改变星系功率谱（小于地平线尺度）。在我们对完整星系功率谱的数值计算中，由于这些非发散校正，我们显示了与标准红移空间功率谱的偏差。我们得出的结论是，随着相对论效应在$ k \ Lessim k_ {eq} $上显着改变了星系功率谱，需要在大规模数据的分析中考虑它们。
We present the galaxy power spectrum in general relativity. Using a novel approach, we derive the galaxy power spectrum taking into account all the relativistic effects in observations. In particular, we show independently of survey geometry that relativistic effects yield no divergent terms (proportional to $k^{-4}P_m(k)$ or $k^{-2}P_m(k)$ on all scales) that would mimic the signal of primordial non-Gaussianity. This cancellation of such divergent terms is indeed expected from the equivalence principle, meaning that any perturbation acting as a uniform gravity on the scale of the experiment cannot be measured. We find that the unphysical infrared divergence obtained in previous calculations occurred only due to not considering all general relativistic contributions consistently. Despite the absence of divergent terms, general relativistic effects represented by non-divergent terms alter the galaxy power spectrum at large scales (smaller than the horizon scale). In our numerical computation of the full galaxy power spectrum, we show the deviations from the standard redshift-space power spectrum due to these non-divergent corrections. We conclude that, as relativistic effects significantly alter the galaxy power spectrum at $k\lesssim k_{eq}$, they need to be taken into account in the analysis of large-scale data.
