It is always interesting to investigate how well can a future experiment perform with respect to others (present or future ones). Cosmology is really an exciting field where a lot of puzzles are still unknown. In this article we consider a generalized dark energy (DE) scenario where anisotropic stress is present. We constrain this generalized cosmic scenario with an aim to investigate how gravitational waves standard sirens (GWSS) may constrain the anisotropic stress, which according to the standard cosmological probes, remains unconstrained. In order to do this, we generate the luminosity distance measurements from $\mathcal{O} (10^3)$ mock GW events which match the expected sensitivity of the Einstein Telescope. Our analyses report that, first of all, GWSS can give better constraints on various cosmological parameters compared to the usual cosmological probes, but the viscous sound speed appearing due to the dark energy anisotropic stress, is totally unconstrained even after the inclusion of GWSS.

中文翻译：

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使用引力波预测暗能量中各向异性应力的约束

研究未来的实验相对于其他实验（现在或未来的实验）的表现如何总是很有趣的。宇宙学确实是一个令人兴奋的领域，其中许多谜题仍然未知。在本文中，我们考虑存在各向异性应力的广义暗能量 (DE) 场景。我们约束这种广义宇宙场景，目的是研究引力波标准警报器 (GWSS) 如何约束各向异性应力，根据标准宇宙学探测器，该应力仍然不受约束。为了做到这一点，我们从 $\mathcal{O} (10^3)​​$ 模拟 GW 事件生成光度距离测量值，这些事件与爱因斯坦望远镜的预期灵敏度相匹配。我们的分析报告说，首先，