Improved Measurement of the Newtonian Gravitational Constant G

The Newtonian gravitational constant, G, is a fundamental constant in nature that is known with the least precision of all fundamental constants. Over the last 200 years, its value has been repeatedly measured, however leading experiments have produced values which are incompatible with one another. Compared to the most precise experiment, some measured values differ by up to 50 times the experimental uncertainty. Recently, improved measurements have been made by two experiments with results that are consistent at the 12 ppm level. After examination of the methodology used in previous measurements, the research group at IUPUI, in collaboration with Cal Poly Humboldt, will use multiple approaches to determine G within a singular torsion pendulum apparatus. We expect to obtain a measurement at the 2 ppm level using these new methods. By continuing the use of a torsion pendulum apparatus, we also hope to better understand the current discrepancies among previous experimental results. This presentation will focus on the motivation behind obtaining a more precise measurement of G, as well as the design and current state of the experiment.