一颗脉冲星在三重恒星系统中的轨道运动的自由落下的普遍性
Anne M Archibald1,2, Nina V Gusinskaia3, Jason W T Hessels3,4
1Anton Pannekoek Institute for Astronomy, University of Amsterdam, Amsterdam, The Netherlands. archibald@astron.nl.
Nature
|July 6, 2018
概括
爱因斯坦
科学领域:
- 引力物理学和天体物理学.
- 一般相对论和其他引力理论的测试.
背景情况:
- 爱因斯坦的广义相对论是基于自由落体的普遍性,
- 强等效原理要求这种普遍性即使对具有显著的自身引力的物体也适用,这是大多数替代引力理论没有满足的条件.
- 之前对这一原理的测试受到太阳系天体的弱自身引力或对脉冲星-白矮星的弱星系引力影响的限制.
研究的目的:
- 在强电场状态下对自由落下的普遍性进行精确的测试.
- 通过使用包含脉冲星和白矮星的独特恒星三重系统来研究强等效原理.
主要方法:
- 使用了PSR J0337+1715恒星三重系统,包括一个毫秒脉冲星的双星和一个围绕另一个白矮星运行的白矮星.
- 对比了脉冲星 (具有强大的自身引力) 和内部白矮星在外部白矮星的引力影响下的加速.
- 测量了加速的分数差异以限制强场Nordtvedt参数.
主要成果:
- 脉冲星及其伴侣白矮星的加速差异不超过2.6×10−6.
- 对强场Nordtvedt参数建立了一个新的严格限制,这是对自由落下的普遍性的衡量.
- 这个极限比之前的太阳系测试和其他强场测试中获得的极限要精确得多.
结论:
- 这些发现为爱因斯坦的广义相对论和自由落体的普遍性提供了强有力的支持,
- 在强大的引力场中测试基本物理学的新工具.
- 在极端的天体物理环境中探测广义相对论的潜在偏差.
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