用微分引力闪测量纳米赫兹引力波的宇宙膨胀
1University of Toronto, University of Toronto, University of Toronto, Canadian Institute for Theoretical Astrophysics, 60 St. George Street, Toronto, ON M5S 3H8, Canada; Department of Physics, 60 St. George Street, Toronto, ON M5S 1A7, Canada; and Dunlap Institute for Astronomy & Astrophysics, AB 120-50 St. George Street, Toronto, ON M5S 3H4, Canada.
Physical review letters
|April 18, 2025
概括
脉冲计时阵列 (PTA) 可以检测超长波长的引力波. 银河系盘引力透镜导致波干扰,使得精确的宇宙膨胀测量和红移距离对推断成为可能.
科学领域:
- 天文学和天体物理学
- 宇宙学的宇宙学是什么?
- 引力波物理 引力波物理
背景情况:
- 脉冲星计时阵列 (PTA) 最近使得超长波长引力波的检测成为可能.
- 引力波为基础科学研究提供了新的机会.
研究的目的:
- 研究引力透镜对PTA检测到的超长波长引力波的影响.
- 探索使用这些透镜效应用于宇宙学测量的潜力.
主要方法:
- 分析银河系盘对PTA源的波透镜效应.
- 建模由此产生的干扰或闪模式.
- 与前景红移信息相关联的镜头图案.
主要成果:
- 预计每个PTA源都会被众多银河系盘的衍射透镜所覆盖.
- 这种透镜诱导引力波应变中的适度调制 (Δh/h∼10^{-3}λ_{1 pc}^{-1}).
- 由此产生的闪模式可以通过连贯的PTA来解决.
结论:
- 对PTA源的衍射透镜提供了一种用于精确测量宇宙膨胀的新方法.
- 未来的PTA实验具有足够的信号对噪声,可以从单个来源推断出数百个红移距离对.
- 这种技术为了解宇宙膨胀历史开辟了新的途径.
相关概念视频
01:17Space-Time Curvature and the General Theory of Relativity
2.6K
In 1905, Albert Einstein published his special theory of relativity. According to this theory, no matter in the universe can attain a speed greater than the speed of light in a vacuum, which thus serves as the speed limit of the universe.
This has been verified in many experiments. However, space and time are no longer absolute. Two observers moving relative to one another do not agree on the length of objects or the passage of time. The mechanics of objects based on Newton's laws of...
This has been verified in many experiments. However, space and time are no longer absolute. Two observers moving relative to one another do not agree on the length of objects or the passage of time. The mechanics of objects based on Newton's laws of...
2.6K
01:21Schwarzschild Radius and Event Horizon
1.9K
No object with a finite mass can travel faster than the speed of light in a vacuum. This fact has an interesting consequence in the domain of extremely high gravitational fields.
The minimum speed required to launch a projectile from the surface of an object to which it is gravitationally bound so that it eventually escapes the object’s gravitational field is called the escape velocity. The escape velocity is independent of the mass of the object. Merging the idea of escape...
The minimum speed required to launch a projectile from the surface of an object to which it is gravitationally bound so that it eventually escapes the object’s gravitational field is called the escape velocity. The escape velocity is independent of the mass of the object. Merging the idea of escape...
1.9K
01:26Influence of Earth's Curvature and Atmospheric Refraction on Leveling
32
During leveling, the Earth's curvature and atmospheric refraction introduce deviations in the line of sight from a true horizontal reference. When the line of sight is leveled, it remains perpendicular to the plumb line only at a single point. Beyond this, it deviates due to the Earth’s curvature, represented by the correction C. For a sight distance D, the deviation can be derived using the relationship:This relationship shows that the deviation increases quadratically with distance.
32