New Test of the Equivalence Principle from Lunar Laser Ranging

This is the authors' abstract. We don't add key points for this paper.

An analysis of six years of lunar-laser-ranging data gives a zero amplitude for the Nordtvedt term in the Earth-Moon distance yielding the Nordtvedt parameter η=0.00±0.03 Thus, Earth's gravitational self-energy contributes equally, ±{}3%, to its inertial mass and passive gravitational mass. At the 70% confidence level this result is only consistent with the Brans-Dicke theory for ω>29. We obtain |β-1|0.02 to 0.05 for five-parameter parametrized post-Newtonian theories of gravitation with energy-momentum conservation, or |β-1|0.01 if only β and γ are considered.