The most important problem in fundamental physics is the description of the contents of the Universe. Today, we know that 95% thereof is totally unknown. Two thirds of that amount is the mysterious Dark Energy described in an interesting and important review [E. J. Copeland, M. Sami and S. Tsujikawa, Int. J. Mod. Phys. D 15 (2006) 1753]. We briefly extend here the ideas contained in that review including the more general Dark Sector, that is, Dark Matter and Dark Energy, eventually composing a new physical Sector. Understanding the Dark Sector with precision is paramount for us to be able to understand all the other cosmological parameters comprehensively as modifications of the modeling could lead to potential biases of inferred parameters of the model, such as measurements of the Hubble constant and distance indicators such as the Baryon Acoustic Oscillations. We discuss several modern methods of observation that can disentangle the different possible descriptions of the Dark Sector. The possible applications of some theoretical developments are also included in this paper as well as a more thorough evaluation of new observational techniques at lower frequencies and gravitational waves.

中文翻译：

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暗区宇宙学

基础物理学中最重要的问题是对宇宙内容的描述。今天，我们知道其中 95% 是完全未知的。其中三分之二是在一篇有趣且重要的评论中描述的神秘暗能量 [EJ Copeland, M. Sami 和 S. Tsujikawa, Int. J.国防部。物理。D 15 (2006) 1753]。我们在这里简要扩展该评论​​中包含的想法，包括更一般的暗扇区，即暗物质和暗能量，最终构成一个新的物理扇区。准确了解暗区对于我们能够全面了解所有其他宇宙学参数至关重要，因为模型的修改可能导致模型推断参数的潜在偏差，例如测量哈勃常数和距离指标，如重子声振荡。我们讨论了几种现代观察方法，这些方法可以解开对黑暗扇区的不同可能描述。本文还包括一些理论发展的可能应用，以及对低频和引力波新观测技术的更全面评估。