Jupiter Light-Deflection Experiment and Its Results Sergei Kopeikin Department of Physics and Astronomy University of Missouri – Columbia Talk given at the MidWest Relativity Meeting (Milwaukee, Wisconsin, October 16)

The Team Edward Fomalont (NRAO) (observation + data processing) Sergei Kopeikin (UMC) (theory + interpretation)

The VLBI Concept

The tested theory of gravitation is to be: based on a variational principle, covariant (the principle of equivalence is valid), admit the gauge freedom of the fields, consistent with matter’s conservation laws, able to predict new observable effects, which have to be unambiguously parameterized.

Acceptable Theories: Einstein’s General Theory of Relativity Scalar-Tensor Theory of Gravity Vector – Tensor Theory of Gravity Warning: the PPN formalism is not a theory (think about this !)

This is a delicate theoretical issue ! An Important Message: Astronomical observations are done with electromagnetic waves of various frequencies. Maxwell’s theory must be properly embodied in and compatible with the theory of gravitation being under the experimental testing. This is a delicate theoretical issue !

Vector – Tensor Theory (T. Jacobson, S. Carlip)

The Gravity Field Equations

Equations of Propagation of Electromagnetic Waves

Electromagnetic Phase

The Two Null Cones

Jupiter Light-Deflection Experiment

Magnitude of the Effect

Resume 10 micro-arcsecond astrometric resolution from the ground has been achieved by the phase-referencing technique with two calibrators; A new time-dependent relativistic effect of the order of (v/c)^3 has been measured; The null characteristics of the gravitational and electromagentic fields coincide with the accuracy of 20% ; The speed of gravity does not exceed the speed of light.