We still don’t have a more precise value for “Big G”

“The NIST team replicated the original BIPM experiment, building a torsion balance with eight metal cylinders: four on a rotating carousel and four smaller masses inside the carousel, sitting on a suspended disk held by a thin ribbon of copper-beryllium. The torsion balance and ribbon would twist when the outer masses attracted the inner ones, and physicists measured Big G by tracking the cylinder’s rotation and the resulting gravitational torque. They also performed a second set of measurements by applying a voltage to electrodes beside the inner masses. This twisted the wire in the opposite direction to the gravitational torque, and the voltage magnitude provided another estimate of Big G.

The NIST scientists also added an extra twist: They ran two versions of the experiment, one with copper masses and one with sapphire masses, achieving nearly identical values for both. This ruled out the possibility that the specific materials used were affecting the measurements“

https://arstechnica.com/science/2026/04/we-still-dont-have-a-more-precise-value-for-big-g/

Interesting that they did this with both copper and sapphire but I thought that the weak equivalence principle had been confirmed at higher precision than this, so what would be the point? (Guess I gotta go read the actual paper)

(edit: quick scan suggests the different materials were used for other reasons - EM properties and mass amount and uniformity)