arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2209.00440astro-ph.CO
收藏

涨落暗能量与光度距离

Fluctuating Dark Energy and the Luminosity Distance

C. J. G. Vedder, E. Belgacem, N. E. Chisari, T. Prokopec

摘要:

推动宇宙加速膨胀的暗能量的起源仍然是个谜。我们探讨的可能性,暗能量波动,导致空间相关性。由于这些波动,哈勃速率本身成为一个波动量。我们讨论的影响,这对测量Ia型超新星,这是用来约束的光度距离。我们表明,光度距离的影响,空间相关性在几个方面。首先,亮度距离被波动修饰,从而不同于标准$Λ$ CDM。第二,角度相关性在光度距离的两点关联函数中变得可见。为了研究后者,我们构造了光度距离涨落的角功率谱。然后,我们进行预测的两个超新星调查,正在进行的暗能量调查(DES)和即将到来的遗产调查的空间和时间(LSST),并比较这种效果与相对论透镜效应扰动$Λ$ CDM。我们发现,信号可以上升以上的透镜效应,LSST可以测试这种效果的参数空间的很大一部分。作为一个例子,这种情况的一个具体实现是,早期宇宙中某些场的量子涨落以可预测的形式在今天的暗能量密度中留下了空间相关性。在这种情况下,由于暗能量密度场的内在量子性质,哈勃速率会波动。我们研究了这个特定模型的信号是否是可测量的,并得出结论,用LSST测试这个模型将是具有挑战性的。然而,考虑到暗能量流体的声速$c_s<1$可以使该模型可观察。

英文摘要:

The origin of dark energy driving the accelerated expansion of the universe is still mysterious. We explore the possibility that dark energy fluctuates, resulting in spatial correlations. Due to these fluctuations, the Hubble rate itself becomes a fluctuating quantity. We discuss the effect this has on measurements of type Ia supernovae, which are used to constrain the luminosity distance. We show that the luminosity distance is affected by spatial correlations in several ways. First, the luminosity distance becomes dressed by the fluctuations, thereby differing from standard $Λ$CDM. Second, angular correlations become visible in the two-point correlation function of the luminosity distance. To investigate the latter we construct the angular power spectrum of luminosity distance fluctuations. We then perform a forecast for two supernova surveys, the ongoing Dark Energy Survey (DES) and the upcoming Legacy Survey of Space and Time (LSST), and compare this effect with relativistic lensing effects from perturbed $Λ$CDM. We find that the signal can rise above the lensing effects and that LSST could test this effect for a large part of the parameter space. As an example, a specific realisation of such a scenario is that quantum fluctuations of some field in the early universe imprint spatial correlations with a predictable form in the dark energy density today. In this case, the Hubble rate fluctuates due to the intrinsic quantum nature of the dark energy density field. We study whether the signal of this specific model would be measurable, and conclude that testing this model with LSST would be challenging. However, taking into account a speed of sound $c_s<1$ of the dark energy fluid can make this model observable.

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。

↑