在DESI 2024之后,昆宇宙学和修改引力
Yuhang Yang1, Xin Ren2, Qingqing Wang1
1Department of Astronomy, School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China; CAS Key Laboratory for Researches in Galaxies and Cosmology, School of Astronomy and Space Science, University of Science and Technology of China, Hefei 230026, China; Deep Space Exploration Laboratory, Hefei 230088, China.
Science bulletin
|August 9, 2024
概括
这项研究使用DESI数据重建了暗能量演变,揭示了"五进制-B"行为,其中暗能量状态方程参数跨越-1.1. 一些修改后的重力理论可以解释这种动态的宇宙膨胀.
科学领域:
- 宇宙学的宇宙学是什么?
- 天体物理学 天体物理学
- 理论物理 理论物理
背景情况:
- 暗能量的性质仍然是现代宇宙学中的主要.
- 了解它的状态方程参数,w(z),对于破译宇宙进化至关重要.
- 动态暗能量模型提供了超出标准宇宙定数 (ΛCDM) 的潜在解释.
研究的目的:
- 在动态暗能量场景下重建宇宙背景进化.
- 为了研究暗能量状态方程参数的行为,w(z).
- 探索在修改引力框架内观察到的暗能量动态的理论基础.
主要方法:
- 利用高斯过程方法进行宇宙背景重建.
- 结合最新的暗能光谱仪器 (DESI) 巴里昂声波振荡 (BAO) 数据.
- 将DESI BAO数据与其他相关的宇宙观测数据结合起来.
- 修改引力理论的重建动作: f (R), f (T) 和 f (Q) 引力.
主要成果:
- 重建的暗能量状态方程参数,w(z),表现出"量子-B"的行为.
- 这种quintom-B行为意味着在w = -1之间,从一个幻影到一个精华般的政权的过渡.
- 一些修改后的重力模型成功地复制了这种五进制动力学,并与DESI数据保持一致.
- 在所有调查的案例中,观察到对标准 ΛCDM 模型的二次偏差有轻微偏好.
结论:
- 宇宙的膨胀可能是由表现出复杂行为的动态暗能量组成部分驱动的.
- 修改的重力理论,特别是某些f (R),f (T) 和f (Q) 重力模型,为观测到的暗能量动态提供了可行的解释.
- 这些发现表明,标准 ΛCDM 模型的扩展可能受到当前的观测数据的支持,特别是来自 DESI.
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