Gravity Probe B and rotational fluid drag

In 1887 the Michelson-Morley experiment looked for a linear "aether wind" and found none. Physics concluded that no medium exists. RSI holds that the null result showed only that instruments built of knots in the medium cannot detect uniform motion through it: rulers shorten and clocks slow by exactly the amounts that hide it, as in the theory of Lorentz and FitzGerald completed by Henri Poincaré.

In 2004, Gravity Probe B used orbiting gyroscopes to measure frame-dragging, the twisting of spacetime by the rotating Earth. It found a drift of about 37 milliarcseconds per year. RSI argues that empty spacetime cannot exert torque, so the drift must be drag within the Eternal Consonance.

The standard formula contains c². In RSI, c² = Ξ/μ, the field's 0.73 N tension divided by its density. Substituting gives a fluid expression. Earth's spin and the medium's density drive the drift, and the tension resists it. Because μ is defined from c, the expression equals General Relativity's and reproduces the measured drift just as GR does; RSI adds the mechanism, and a test that separates the two remains to be designed.

The size of the drift matters. It is roughly one ten-billionth of the Earth's own spin, so the spinning Earth stirs the medium only very slightly. Stellar aberration shows separately that light is not carried along with the Earth's orbit. Rotation, unlike uniform motion, can be registered against the medium, and the gyroscopes detected that slight stirring.