Oblate Sun Supports Scalar‐Tensor Theory
DOI: 10.1063/1.3034265
One of the three classical tests of Einstein’s gravitational theory has been its prediction of Mercury’s orbit; the Einstein value agreed with observations to within 1%. Now measurements by Robert H. Dicke and Mark Goldenberg of Princeton University show that the sun is slightly elliptical in shape. The quadrupole moment indicated by such a solar oblateness would perturb Mercury’s motion and could account for 8% of the classical excess in the precession of Mercury’s perihelion; this would imply an 8% discrepancy in the Einstein value. The other two tests of Einstein’s theory are the gravitational red shift, which is also predicted by other theories, and the gravitational deflection of light, which is poorly known.
