※ 引述《s1290961 (煦)》之铭言： : 最近写了一篇谈广相的文章， : 有兴趣的话欢迎阅读、讨论。 : https://sciencebrunch.wordpress.com/2016/01/22/%E9%80%9A%E5%BE%80%E5%BB%A3%E7%BE%A9%E7%9B%B8%E5%B0%8D%E8%AB%96%E4%B9%8B%E8%B7%AF%E2%94%80%E2%94%80%E7%89%9B%E9%A0%93%E3%80%81%E9%A6%AC%E8%B5%AB%E3%80%81%E6%84%9B%E5%9B%A0%E6%96%AF%E5%9D%A6/ : 缩网址：https://goo.gl/BMXMgw 稍微看一下写得还蛮认真很仔细的,不过有些地方我觉得有点问题提出来跟板友 分享看看,首先我们要知道以现代的广义相对论来看Mach原理跟广义相对论是不太一样 的喔,Mach原理对爱因斯坦的确早期有启发性的关键,但是後来这二个发展是不太一样的 这二件事情是要被分开看待的,而且二者都有实验来验证,爱因斯坦广相实验的全部被证实 目前学术界的看法是支持爱因斯坦的广义相对论而不支持Mach原理 Mach原理是说 不存在绝对时空,惯性系是物体相对於宇宙整体的平均做加速运动的座标系 而物体的惯性效应是由於宇宙间星系的物质分布和运动所决定 那Mach原理所导致的必然结果是 1.在比较重的物体,物体的惯性应该增加 2.当周围的物体加速运动时候,此物体应该受到与此物体加速度同样方向的加速度方向 後来1960年代有二个物学家Vernon W. Hughes和 Ronald Drever 做了质量各异 向性的实验来验证Mach原理 https://en.wikipedia.org/wiki/Hughes%E2%80%93Drever_experiment Vernon W. Hughes et al. (1960)[3] and Ronald Drever (1961)[4] independently conducted similar spectroscopic experiments to test Mach's principle. However, they didn't use the Mossbauer effect but made magnetic resonance measurements of the nucleus of lithium-7, whose ground state possesses a spin of 3/2. The ground state is split into four equally spaced magnetic energy levels when measured in a magnetic field in accordance with its allowed magnetic quantum number. The nuclear wave functions for the different energy levels have different spatial distributions relative to the magnetic field, and thus have different directional properties. If mass isotropy is satisfied, each transition between a pair of adjacent levels should emit a photon of equal frequency, resulting in a single, sharp spectral line. On the other hand, if inertia has a directional dependence, a triplet or broadened resonance line should be observed. During the 24-hour course of Drever's version of the experiment, the Earth turned,and the magnetic field axis swept different sections of the sky. Drever paid particular attention to the behavior of the spectral line as the magnetic field crossed the center of the galaxy.[A 7] Neither Hughes nor Drever observed any frequency shift of the energy levels, and due to their experiments' high precision, the maximum anisotropy could be limited to 0.04 Hz = 10^-25 GeV. 简单来说就是 Mach原理认为是认为较大质量的物体假设较大惯性效应,那假设这大质量是银河系 且银河系质量各异向性的,则粒子朝着银河系和离开银河系惯性质量会稍有不同 Hughes和Drever用lithium-7做实验观察在H=4700 Gauss的磁场下原子核的共振光谱 根据Zeeman效应,磁量子数 J=3/2在磁场中分裂有 m_J= 3/2,1/2,-1/2,-3/2四条光谱 如果惯性质量是量各异向性的,则这四个态是不等间隔的,因为不同的m_J相当於磁偶极矩 对磁场有不同的方向,则电子有不同的运动方向,则这四个光谱间隔距离应该是不一样 但是并没有量到这个效应. 事实上还有一个理论是更希望超越广义相对论来支持Mach原理,就是着名的 Dicke-Brans理论,这是科学史上着名的典范理论,就是这理论很美但是实验并不支持 有机会在po一篇orz --

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