Finding the absolute velocity of a reference frame or solar system
     One might think it should be easy to determine our motion through a qm if the motion has the significant effects on clocks, distance scales, and masses described above. Although many experiments may appear capable of detecting absolute motion (e.g. Michelson's 1887 experiment), careful analysis shows why most of the experiments will not work.
     Nevertheless, there appear to be viable ways to determine absolute motion. For example, changes in our absolute motion as Earth rotates and revolves around the Sun should affect experimental determinations of the gravitational constant, G, because the changes in absolute motion change the geometry of the experimental apparatus. We will now consider how the measured value of G depends on the orientation of the measuring apparatus relative to its direction of absolute velocity.
     Figure 12 shows a 10 m x 10 m laboratory which is located in inertial reference frame B of Fig. 1 and therefore has a .6 ca absolute velocity. The lab contains an apparatus for determining the gravitational constant, G. The apparatus consists of two stationary masses, My and Mx, anchored near the y and x walls of the lab, and one moveable mass, Mxy, secured to one end of a rigid swing arm. The other end of the swing arm is secured to shaft, P, which is mounted perpendicular to the xy plane of the lab. Shaft, P, is free to rotate so that the swing arm and Mxy can swing from the y-direction orientation shown in Fig. 12 to an x-direction orientation (shown via dotted lines). As Mxy is moved from My to Mx, the distance between the centers of Mxy and P changes from 6 ma to rv·6 ma, as shown. The three identical masses are 1 ma diameter aluminum spheres when at rest in the qm. In the lab of Fig. 12, the spheres are foreshortened by the ratio rv or .8, as shown, and each has a mass of M kga (about 1767 kga).
     Observers in the lab determine the gravitational constant, G, by measuring the torque on shaft, P, required to separate Mxy from My. According to Eq. (1), the gravitational force between Mxy and My is Fy=M²·G/rv² absolute newtons (because the distance between the centers of the masses is 1·rv ma). When Mxy is swung over to mass Mx, the gravitational force between Mxy and Mx is Fx=M²·G/1² or only rv² as large as Fy if Eq. (1) is valid in the lab of Fig. 12. If the gravitational forces between the masses are due to gradients of photon-slowing radiation from the masses (as discussed in connection with Premise II), the gradients will be somewhat different in the Fy and Fx cases due to the lab's absolute velocity. Therefore, the ratio Fx/Fy is uncertain, but it is probably between rv² and 1.
     The torque on shaft, P, needed to separate masses Mxy and My is Ty=Fy·6 (absolute newton meters), and the torque on P needed to separate masses Mxy and Mx is Tx=Fx·rv·6. The ratio Tx/Ty equals rv·Fx/Fy, or somewhere between rv and rv³ (depending on the ratio Fx/Fy). Therefore, observers in the lab will find that the torque on P necessary to separate the masses depends on the swing arm's orientation in the lab. The torque (and thus the measured value of G) also depends on the lab's orientation in inertial reference frame B of Fig. 1.
     On Earth, where the direction and magnitude of a lab's absolute velocity constantly change due to Earth's rotation and revolution, measurements of the gravitational constant should vary by a factor of (1-rv) to (1-rv³). If Earth's absolute velocity is va=.0012 ca (as indicated by the asymmetry of CMB radiation), Earth's rv from Eq. (8) is about rv=.9999993, and rv³=.9999978. Therefore we could expect that measurements of G will vary by a factor of .0000007 to .0000022, and that the measurements of G will be in agreement to no better than five or six significant figures.
     In recent years, experimental measurements of G made at various locations on Earth have not resulted in a consensus value for G that is better than four significant figures. Variations in the geometry of experimental apparatus, as discussed above, may be contributing to the inability to make a more precise determination of G. Further experiments to measure G and variations in G (and the study of data from past experiments) should show whether or not experimental apparatus is affected by motion through the qm and whether or not the Sun has an absolute velocity of .0012 ca as indicated by the CMB radiation.