Null test of the gravitational inverse square law of gravitation

Abstract

An experiment has been performed to demonstrate a new source-independent null test of the inverse square law of gravitation. A single-axis superconducting gravity gradiometer was rotated into three orthogonal orientations to measure the Laplacian of the gravitational potential produced by a 1600-kg lead pendulum at an average distance of 2.3 m. The result is that if one assumes a potential of the form <i>ϕ</i> (r) = − (GM / r) [1 + α exp (−μr)], the value of α is + 0.024±0.036 at μ⁻¹ = 1m.