在毫米尺度的原子样本上解析引力红移
Tobias Bothwell1, Colin J Kennedy2,3, Alexander Aeppli2
1JILA, National Institute of Standards and Technology and University of Colorado, Department of Physics, University of Colorado, Boulder, CO, USA. tobias.bothwell@colorado.edu.
Nature
|February 17, 2022
概括
科学家测量了超冷的原子中的重力红移, 证实了爱因斯坦
科学领域:
- 原子物理
- 一般相对论
- 量子力学
背景情况:
- 爱因斯坦的广义相对论预测引力红移,
- 原子钟对于测试各种距离尺度上的广义相对论至关重要.
- 未来的原子钟旨在探讨广义相对论和量子力学的交叉点.
研究的目的:
- 测量超冷原子的毫米尺度样本中的重力红移.
- 提升原子钟的灵敏度, 探索基本物理.
主要方法:
- 在毫米尺度样本中使用了超冷的原子.
- 获得了7.6 × 10-21的分数频率测量不确定性,这是10倍以上的改进.
- 测量了与引力红移一致的线性频率梯度.
主要成果:
- 在毫米尺度样本中显示出可测量的引力红移.
- 在原子钟频率方面实现了前所未有的测量不确定性.
- 观察到因引力电位差异而产生的线性频率梯度.
结论:
- 结果证实了爱因斯坦在毫米尺度上对引力红移的预测.
- 这一进步开启了原子钟的新时代,
- 这为原子钟探测量子引力系统铺平了道路.
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