Gravity Probe B and the Geodetic Precession of an Orbiting Gyroscope as a Frame Test

This paper computes the geodetic precession rate for superconducting gyroscopes in polar Earth orbit aboard Gravity Probe B within a torsion-regulated gravitational frame — Einstein-Cartan gravity with the density bound that follows from its spin-torsion term — and compares the result with the best published measurement. The relativistic prediction is 6638 milliarcsec per year; the published value is 6602 plus or minus 18.3 milliarcsec per year, a residual of -35.75 milliarcsec per year (-1.953 standard deviations). Because torsion in this framework is sourced only by spin density and does not propagate, the predicted deviation from general relativity is set by the square root of the ratio of the system density to the bound density, giving a fractional deviation of 7.533e-28 and a correction of 5e-24 milliarcsec per year. The measurement bounds any fractional deviation at 0.0109 (two standard deviations), so the framework passes this test with a headroom factor of 1.447e+25. Stated plainly, the test is consistent with the framework but cannot distinguish it from general relativity; the implied lower bound on the density scale, 4.641e+07 kilograms per cubic metre, lies far below the framework's bound of 9.718e+57 kilograms per cubic metre. The study is computed from stated assumptions and published data; it is simulated, not measured.