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arXiv 1811.00529astro-ph.COgr-qc
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综合Sachs-Wolfe效应测量中的宇宙方差缓和

Cosmic variance mitigation in measurements of the integrated Sachs-Wolfe effect

Simon Foreman, P. Daniel Meerburg, Joel Meyers, Alexander van Engelen

摘要:

宇宙微波背景(CMB)对宇宙加速膨胀的最新阶段非常敏感,它通过后期积分的Sachs-Wolfe(ISW)效应表现为大角度尺度上的次级温度起伏。然而,来自原始CMB波动的巨大宇宙变化限制了这种效应在约束暗能量或修正引力方面的有用性。在本文中,我们提出了一种新的方法来分离的ISW信号从主信号使用引力透镜,基于这样的事实,即ISW信号是,一个很好的近似,不引力透镜。我们预测如何以及我们可以隔离不同的实验配置的ISW信号,并讨论了各种应用,包括修改的重力,大规模的CMB异常,并测量本地型原始非高斯。虽然目前的实验还无法实现,但所提出的方法是一种独特的方法,可以消除主要信号的宇宙方差,从而比以前认为的更好地对后期现象进行基于CMB的约束。

英文摘要:

The cosmic microwave background (CMB) is sensitive to the recent phase of accelerated cosmic expansion through the late-time integrated Sachs-Wolfe (ISW) effect, which manifests as secondary temperature fluctuations on large angular scales. However, the large cosmic variance from primary CMB fluctuations limits the usefulness of this effect in constraining dark energy or modified gravity. In this paper, we propose a novel method to separate the ISW signal from the primary signal using gravitational lensing, based on the fact that the ISW signal is, to a good approximation, not gravitationally lensed. We forecast how well we can isolate the ISW signal for different experimental configurations, and discuss various applications, including modified gravity, large-scale CMB anomalies, and measurements of local-type primordial non-Gaussianity. Although not within reach of current experiments, the proposed method is a unique way to remove the cosmic variance of the primary signal, allowing for better CMB-based constraints on late-time phenomena than previously thought possible.

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。

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